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Publications
Reprint request
by conventional mail or by email to:
ETH Zurich
Marianne Wettstein
Professorship Crop Science
LFW, C 55.1
Universitätstrasse 2
8092 Zürich
Switzerland
Fax: +41 44 632 11 43
Group of Crop Science
Advanced phenotyping offers opportunities for improved breeding of forage and turf species
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Walter, Achim, Studer, Bruno, Koelliker, Roland,
2012
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| Author(s): | Walter, Achim, Studer, Bruno, Koelliker, Roland |
| Title: | Advanced phenotyping offers opportunities for improved breeding of forage and turf species |
| Abstract: | Background and Aims: Advanced phenotyping, i.e. the application of automated, high-throughput methods to characterize plant architecture and performance, has the potential to accelerate breeding progress but is far from being routinely used in current breeding approaches. In forage and turf improvement programmes, in particular, where breeding populations and cultivars are characterized by high genetic diversity and substantial genotype × environment interactions, precise and efficient phenotyping is essential to meet future challenges imposed by climate change, growing demand and declining resources. Scope: This review highlights recent achievements in the establishment of phenotyping tools and platforms. Some of these tools have originally been established in remote sensing, some in precision agriculture, while others are laboratory-based imaging procedures. They quantify plant colour, spectral reflection, chlorophyll-fluorescence, temperature and other properties, from which traits such as biomass, architecture, photosynthetic efficiency, stomatal aperture or stress resistance can be derived. Applications of these methods in the context of forage and turf breeding are discussed. Conclusions: Progress in cutting-edge molecular breeding tools is beginning to be matched by progress in automated non-destructive imaging methods. Joint application of precise phenotyping machinery and molecular tools in optimized breeding schemes will improve forage and turf breeding in the near future and will thereby contribute to amended performance of managed grassland agroecosystems. |
| Published in: | Annals of botany |
| Volume: | 110 |
| Issue: | 6 |
| Pages: | 1271 - 1279 |
| ISSN: | 0305-7364, 0003-4754, 1095-8290 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Oxford |
| Publication status: | Published |
| Subjects: | Botanik |Botany , Forage, Turf, Breeding, Phenotyping, Growth, Biomass, Imaging, Marker-assisted selection, Remote sensing |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Forage, Turf, Breeding, Phenotyping, Growth, Biomass, Imaging, Marker-assisted selection, Remote sensing |
| DBID source: | FORM-1346071299, WOS-000310371800018 |
| DOI: | 10.1093/aob/mcs026 |
| Nebis system number: | 000033951 |
Diel patterns of leaf and root growth: endogenous rhythmicity or environmental response?
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Tom Ruts, Shizue Matsubara, Anika Wiese-Klinkenberg and Achim Walter,
2012
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| Author(s): | Tom Ruts, Shizue Matsubara, Anika Wiese-Klinkenberg and Achim Walter |
| Title: | Diel patterns of leaf and root growth: endogenous rhythmicity or environmental response? |
| Published in: | Journal of experimental botany |
| Volume: | 63 |
| Issue: | 9 |
| Pages: | 3339 - 3351 |
| Publication date / Date received: | 2012-01-01 |
| Language: | English |
| DBID source: | FORM-1346071867 |
High-to-Low CO2 Acclimation Reveals Plasticity of the Photorespiratory Pathway and Indicates Regulatory Links to Cellular Metabolism of Arabidopsis
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Timm, Stefan, Mielewczik, Michael, Florian, Alexandra, Frankenbach, Silja, Dreissen, Anne, Hocken, Nadine, Fernie, Alisdair R., Walter, Achim, Bauwe, Hermann,
2012
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| Author(s): | Timm, Stefan, Mielewczik, Michael, Florian, Alexandra, Frankenbach, Silja, Dreissen, Anne, Hocken, Nadine, Fernie, Alisdair R., Walter, Achim, Bauwe, Hermann |
| Title: | High-to-Low CO2 Acclimation Reveals Plasticity of the Photorespiratory Pathway and Indicates Regulatory Links to Cellular Metabolism of Arabidopsis |
| Abstract: | Background: Photorespiratory carbon metabolism was long considered as an essentially closed and nonregulated pathway with little interaction to other metabolic routes except nitrogen metabolism and respiration. Most mutants of this pathway cannot survive in ambient air and require CO2-enriched air for normal growth. Several studies indicate that this CO2 requirement is very different for individual mutants, suggesting a higher plasticity and more interaction of photorespiratory metabolism as generally thought. To understand this better, we examined a variety of high- and low-level parameters at 1% CO2 and their alteration during acclimation of wild-type plants and selected photorespiratory mutants to ambient air. Methodology and Principal Findings: The wild type and four photorespiratory mutants of Arabidopsis thaliana (Arabidopsis) were grown to a defined stadium at 1% CO2 and then transferred to normal air (0.038% CO2). All other conditions remained unchanged. This approach allowed unbiased side-by-side monitoring of acclimation processes on several levels. For all lines, diel (24 h) leaf growth, photosynthetic gas exchange, and PSII fluorescence were monitored. Metabolite profiling was performed for the wild type and two mutants. During acclimation, considerable variation between the individual genotypes was detected in many of the examined parameters, which correlated with the position of the impaired reaction in the photorespiratory pathway. Conclusions: Photorespiratory carbon metabolism does not operate as a fully closed pathway. Acclimation from high to low CO2 was typically steady and consistent for a number of features over several days, but we also found unexpected short-term events, such as an intermittent very massive rise of glycine levels after transition of one particular mutant to ambient air. We conclude that photorespiration is possibly exposed to redox regulation beyond known substrate-level effects. Additionally, our data support the view that 2-phosphoglycolate could be a key regulator of photosynthetic-photorespiratory metabolism as a whole. |
| Published in: | PLoS ONE |
| Volume: | 7 |
| Issue: | 8 |
| Pages: | e42809 |
| ISSN: | 1932-6203 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Published |
| Subjects: | Medizin und Gesundheitswesen allgemein|Medicine and Health, General |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | FORM-1346075199, WOS-000308063700024 |
| DOI: | 10.1371/journal.pone.0042809 |
| Nebis system number: | 006206116 |
Competitive underutilized crops will depend on the state funding of breeding programmes: an opinion on the example of Europe
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Stamp, Peter, Messmer, Rainer, Walter, Achim,
2012
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| Author(s): | Stamp, Peter, Messmer, Rainer, Walter, Achim |
| Title: | Competitive underutilized crops will depend on the state funding of breeding programmes: an opinion on the example of Europe |
| Published in: | Plant Breeding |
| Volume: | 131 |
| Pages: | 461 - 464 |
| Publication date / Date received: | 2012-01-01 |
| DBID source: | FORM-1357808167 |
| DOI: | 10.1111/j.1439-0523.2012.01990.x |
Competitive underutilized crops will depend on the state funding of breeding programmes
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Stamp, Peter, Messmer, Rainer, Walter, Achim,
2012
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| Author(s): | Stamp, Peter, Messmer, Rainer, Walter, Achim |
| Title: | Competitive underutilized crops will depend on the state funding of breeding programmes |
| Subtitle: | An opinion on the example of Europe |
| Abstract: | Today, food security depends on very few major grain crops, actually an outcome of breeding success and globalization. This will not change in the near future. But action must be taken to stop the unprecedented pace of the erosion of biodiversity on arable fields; this is a prerequisite to ensure robust cropping systems as well as complementary food production for coming generations. Although this has been discussed for decades, little progress has been made. Most underutilized crops are no longer suitable for todays agriculture. Success can be achieved only by planning long-term breeding programmes instead of screening underutilized crops again and again. This cannot be realized, however, by market-driven private breeders. State funding is mandatory to launch a programme of a set of well-chosen crops. Guidelines are provided, based on case examples from cool temperate regions, where promising crops undergo stepwise selection process. In Europe, a programme could be established in the frame of a virtual institute, wisely investing a small part of the direct payments that go to farmers today, thereby safeguarding their future. |
| Published in: | Plant Breeding |
| Volume: | 131 |
| Issue: | 4 |
| Pages: | 461 - 464 |
| ISSN: | 0179-9541, 1439-0523 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Acker- und Futterbau (inkl. Kultur- und Nutzpflanzen) | Crop and Fodder Farming (incl. Cultivated and Crop Plants), Underutilized crops, Alternative crops, Long-term breeding |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Underutilized crops, Alternative crops, Long-term breeding |
| DBID source: | WOS-000306406900001, FORM-1357808167 |
| DOI: | 10.1111/j.1439-0523.2012.01990.x |
| Nebis system number: | 000034603 |
Diel patterns of leaf and root growth
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Ruts, Tom, Matsubara, Shizue, Wiese-Klinkenberg, Anika, Walter, Achim,
2012
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| Author(s): | Ruts, Tom, Matsubara, Shizue, Wiese-Klinkenberg, Anika, Walter, Achim |
| Title: | Diel patterns of leaf and root growth |
| Subtitle: | Endogenous rhythmicity or environmental response? |
| Abstract: | Plants are sessile organisms forced to adjust to their surrounding environment. In a single plant the photoautotrophic shoot is exposed to pronounced environmental variations recurring in a day-night 24 h (diel) cycle, whereas the heterotrophic root grows in a temporally less fluctuating environment. The contrasting habitats of shoots and roots are reflected in different diel growth patterns and their responsiveness to environmental stimuli. Differences between diel leaf growth patterns of mono- and dicotyledonous plants correspond to their different organization and placement of growth zones. In monocots, heterotrophic growth zones are organized linearly and protected from the environment by sheaths of older leaves. In contrast, photosynthetically active growth zones of dicot leaves are exposed directly to the environment and show characteristic, species-specific diel growth patterns. It is hypothesized that the different exposure to environmental constraints and simultaneously the sink/source status of the growing organs may have induced distinct endogenous control of diel growth patterns in roots and leaves of monocot and dicot plants. Confronted by strong temporal fluctuations in environment, the circadian clock may facilitate robust intrinsic control of leaf growth in dicot plants. |
| Published in: | Journal of experimental botany |
| Volume: | 63 |
| Issue: | 9 |
| Pages: | 3339 - 3351 |
| ISSN: | 0022-0957, 1460-2431 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Oxford |
| Publication status: | Published |
| Subjects: | Carbohydrate, Circadian, Dicot, Diurnal, Environment, Growth, Leaf, Monocot, Regulation, Root |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Carbohydrate, Circadian, Dicot, Diurnal, Environment, Growth, Leaf, Monocot, Regulation, Root |
| DBID source: | WOS-000304836300003, FORM-1346071867 |
| DOI: | 10.1093/jxb/err334 |
| Nebis system number: | 000049325 |
The Leaf Reticulate Mutant dov1 Is Impaired in the First Step of Purine Metabolism
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Rosar, Christian, Kanonenberg, Kerstin, Nanda, Arun M., Mielewczik, Michael, Bräutigam, Andrea, Novak, Ondrej, Strnad, Miroslav, Walter, Achim, Weber, Andreas P.M.,
2012
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| Author(s): | Rosar, Christian, Kanonenberg, Kerstin, Nanda, Arun M., Mielewczik, Michael, Bräutigam, Andrea, Novak, Ondrej, Strnad, Miroslav, Walter, Achim, Weber, Andreas P.M. |
| Title: | The Leaf Reticulate Mutant dov1 Is Impaired in the First Step of Purine Metabolism |
| Abstract: | A series of reticulated Arabidopsis thaliana mutants were previously described. All mutants show a reticulate leaf pattern, namely green veins on a pale leaf lamina. They have an aberrant mesophyll structure but an intact layer of bundle sheath cells around the veins. Here, we unravel the function of the previously described reticulated EMS-mutant dov1 (differential development of vascular associated cells 1). By positional cloning, we identified the mutated gene, which encodes glutamine phosphoribosyl pyrophosphate aminotransferase 2 (ATase2), an enzyme catalyzing the first step of purine nucleotide biosynthesis. dov1 is allelic to the previously characterized cia1-2 mutant that was isolated in a screen for mutants with impaired chloroplast protein import. We show that purine-derived total cytokinins are lowered in dov1 and crosses with phytohormone reporter lines revealed differential reporter activity patterns in dov1. Metabolite profiling unraveled that amino acids that are involved in purine biosynthesis are increased in dov1. This study identified the molecular basis of an established mutant line, which has the potential for further investigation of the interaction between metabolism and leaf development. |
| Published in: | Molecular plant |
| Volume: | 5 |
| Issue: | 6 |
| Pages: | 1227 - 1241 |
| ISSN: | 1674-2052, 1752-9867 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Oxford |
| Publication status: | Published |
| Subjects: | Biochemie, Molekularbiologie und Zellbiologie|Biochemistry, Molecular Biology and Cell Biology, Botanik |Botany |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | FORM-1346072310 |
| DOI: | 10.1093/mp/sss045 |
| Nebis system number: | 005962904 |
Quantitative mapping of averaged focal adhesion dynamics in migrating cells by shape normalization
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Möhl, Christoph, Kirchgessner, Norbert, Schäfer, Claudia, Hoffman, Bernd, Merkel, Rudolf,
2012
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| Author(s): | Möhl, Christoph, Kirchgessner, Norbert, Schäfer, Claudia, Hoffman, Bernd, Merkel, Rudolf |
| Title: | Quantitative mapping of averaged focal adhesion dynamics in migrating cells by shape normalization |
| Abstract: | The spatially ordered formation and disassembly of focal adhesions is a basic requirement for effective cell locomotion. Because focal adhesions couple the contractile actin–myosin network to the substrate, their distribution determines the pattern of traction forces propelling the cell in a certain direction. In the present study, we quantitatively analyzed the spatial patterning of cell–substrate adhesion in migrating cells by mapping averaged focal adhesion growth dynamics to a standardized cell coordinate system. These maps revealed distinct zones of focal adhesion assembly, disassembly and stability and were strongly interrelated with corresponding actin flow and traction force patterns. Moreover, the mapping technique enables precise detection of even minute responses of adhesion dynamics upon targeted signaling perturbations. For example, the partial inhibition of vinculin phosphorylation was followed by the reduced number of newly formed adhesions, whereas growth dynamics of existing adhesions remained unaffected. |
| Published in: | Journal of cell science |
| Volume: | 125 |
| Issue: | 1 |
| Pages: | 155 - 165 |
| ISSN: | 0021-9533, 1477-9137 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Cambridge |
| Publication status: | Published |
| Subjects: | Biochemie, Molekularbiologie und Zellbiologie|Biochemistry, Molecular Biology and Cell Biology, Actin flow, Cell migration, Focal adhesion dynamics, Traction force |
| Language: | English |
| Keyword: | Actin flow, Cell migration, Focal adhesion dynamics, Traction force |
| DBID source: | FORM-1357806900, WOS-000300329100015 |
| DOI: | 10.1242/jcs.090746 |
| Nebis system number: | 000977877 |
Rapid adjustment in chrysanthemum carbohydrate turnover and growth activity to a change in time-of-day application of light and daylength
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Kjaer, Kathrine Heinsvig, Poiré, Richard, Ottosen, Carl-Otto, Walter, Achim,
2012
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| Author(s): | Kjaer, Kathrine Heinsvig, Poiré, Richard, Ottosen, Carl-Otto, Walter, Achim |
| Title: | Rapid adjustment in chrysanthemum carbohydrate turnover and growth activity to a change in time-of-day application of light and daylength |
| Abstract: | Diel (24 h) rhythms are believed to be of great importance to plant growth and carbohydrate metabolism in fluctuating environments. However, it is unclear how plants that have evolved to experience regular day–night patterns will respond to irregular light environments that disturb diurnally-regulated parameters related to growth. In this study, chrysanthemum plants were exposed to a change in the time-of-day application of light followed by short days or long days with a night interruption of light. We observed a clear shift in the diel cycle of sucrose turnover and relative leaf expansion, indicating a resetting of these activities with a temporal trigger in the early morning. The starch pool was relatively stable in long-day plants and marginally affected by the change in the time-of-day application in light followed by long days with a night interruption. This was in contrast with an onset of a daily starch turnover by a shift to short days. These results confirm findings from model species on the complex relationship between carbohydrate metabolism, source–sink relations and growth rate and they shed new light on the dynamic processes during acclimation towards altered environmental responses of plants in fluctuating environments. |
| Published in: | Functional plant biology |
| Volume: | 39 |
| Issue: | 8 |
| Pages: | 639 - 649 |
| ISSN: | 1445-4408 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Collingwood |
| Publication status: | Published |
| Subjects: | Botanik |Botany , Diurnal regulation, Carbohydrate metabolism, Photosynthesis, Sugar sensing |
| Language: | English |
| Keyword: | Diurnal regulation, Carbohydrate metabolism, Photosynthesis, Sugar sensing |
| DBID source: | FORM-1357806472, WOS-000307520200002 |
| DOI: | 10.1071/FP11289 |
| Nebis system number: | 004240289 |
Nutrient acquisition from arable subsoils in temperate climates
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Kautz, Timo, et al., Walter, Achim,
2012
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| Author(s): | Kautz, Timo, et al., Walter, Achim |
| Title: | Nutrient acquisition from arable subsoils in temperate climates |
| Subtitle: | A review |
| Published in: | Soil Biology and Biochemistry |
| Volume: | 15 |
| Pages: | 1 - 20 |
| ISSN: | 0038-0717 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Accepted |
| Subjects: | Bodenkunde|Soil Science, Oekologie|Ecology |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | FORM-1357751417 |
| Nebis system number: | 000036683 |
Can we improve heterosis for root growth of maize by selecting parental inbred lines with different temperature behaviour?
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Hund, Andreas, Reimer, Regina, Stamp, Peter, Walter, Achim,
2012
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| Author(s): | Hund, Andreas, Reimer, Regina, Stamp, Peter, Walter, Achim |
| Title: | Can we improve heterosis for root growth of maize by selecting parental inbred lines with different temperature behaviour? |
| Published in: | Philosophical Transactions of the Royal Society B: Biological Sciences |
| Volume: | 367 |
| Issue: | 1595 |
| Pages: | 1580 - 1588 |
| Publication date / Date received: | 2012-01-01 |
| DBID source: | FORM-1357750584 |
Can we improve heterosis for root growth of maize by selecting parental inbred lines with different temperature behaviour?
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Hund, Andreas, Reimer, Regina, Stamp, Peter, Walter, Achim,
2012
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| Author(s): | Hund, Andreas, Reimer, Regina, Stamp, Peter, Walter, Achim |
| Title: | Can we improve heterosis for root growth of maize by selecting parental inbred lines with different temperature behaviour? |
| Abstract: | Tolerance to high and low temperature is an important breeding aim for Central and Northern Europe, where temperature fluctuations are predicted to increase. However, the extent to which genotypes differ in their response to the whole range of possible temperatures is not well understood. We tested the hypothesis that the combination of maize (Zea mays L.) inbred lines with differing temperature optima for root growth would lead to superior hybrids. This hypothesis is based on the concept of 'marginal overdominance' in which the hybrid expresses higher relative fitness than its parents, summed over all situations. The elongation rates of axile and lateral roots of the reciprocal cross between two flint and two dent inbred lines were assessed at temperatures between 15 degrees C and 40 degrees C. Indeed, the cross between UH005 and UH250 with lateral root growth temperature optima at 34 degrees C and 28 degrees C, respectively, resulted in intermediate hybrids. At temperatures below and above 31 degrees C, the hybrids' root growth was comparable to the better parent, respectively, thereby increasing temperature tolerance of the hybrid compared with its parents. The implications of and reasons for this heterosis effect are discussed in the context of breeding for abiotic stress tolerance and of putatively underlying molecular mechanisms. This finding paves the way for more detailed investigations of this phenomenon in future studies. |
| Published in: | Philosophical transactions of the Royal Society. B, Biological sciences |
| Volume: | 367 |
| Issue: | 1595 |
| Pages: | 1580 - 1588 |
| ISSN: | 0962-8436, 1471-2970 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | London |
| Publication status: | Published |
| Subjects: | Biologie allgemein|Biology, General, Flint, Dent, Corn, Marginal overdominance, Root, Abiotic stress |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Flint, Dent, Corn, Marginal overdominance, Root, Abiotic stress |
| DBID source: | WOS-000303107900016, FORM-1357750584 |
| DOI: | 10.1098/rstb.2011.0242 |
| Nebis system number: | 000558205 |
Repression of early lateral root initiation events by transient water deficit in barley and maize
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Babé, Aurélie, Lavigne, Tristan, Séverin, Jean-Philippe, Nagel, Kerstin A., Walter, Achim, Chaumont, François, Batoko, Henri, Beeckman, Tom, Draye, Xavier,
2012
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| Author(s): | Babé, Aurélie, Lavigne, Tristan, Séverin, Jean-Philippe, Nagel, Kerstin A., Walter, Achim, Chaumont, François, Batoko, Henri, Beeckman, Tom, Draye, Xavier |
| Title: | Repression of early lateral root initiation events by transient water deficit in barley and maize |
| Abstract: | The formation of lateral roots (LRs) is a key driver of root system architecture and developmental plasticity. The first stage of LR formation, which leads to the acquisition of founder cell identity in the pericycle, is the primary determinant of root branching patterns. The fact that initiation events occur asynchronously in a very small number of cells inside the parent root has been a major difficulty in the study of the molecular regulation of branching patterns. Inducible systems that trigger synchronous lateral formation at predictable sites have proven extremely valuable in Arabidopsis to decipher the first steps of LR formation. Here, we present a LR repression system for cereals that relies on a transient water-deficit treatment, which blocks LR initiation before the first formative divisions. Using a time-lapse approach, we analysed the dynamics of this repression along growing roots and were able to show that it targets a very narrow developmental window of the initiation process. Interestingly, the repression can be exploited to obtain negative control root samples where LR initiation is absent. This system could be instrumental in the analysis of the molecular basis of drought-responsive as well as intrinsic pathways of LR formation in cereals. |
| Published in: | Philosophical transactions of the Royal Society. B, Biological sciences |
| Volume: | 367 |
| Issue: | 1595 |
| Pages: | 1534 - 1541 |
| ISSN: | 0962-8436, 1471-2970 |
| Publication date / Date received: | 2012-01-01 |
| Publication status: | London |
| Publication status: | Published |
| Subjects: | Biologie allgemein|Biology, General, Lateral root initiation, Water deficit, Barley, Maize |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Lateral root initiation, Water deficit, Barley, Maize |
| DBID source: | FORM-1346074696 |
| DOI: | 10.1098/rstb.2011.0240 |
| Nebis system number: | 000558205 |
Temporal dynamics of kernel set of tropical sweet maize (Zea mays L.) as influenced by genotype and mild drought
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Rupitak, Quanjai, Stamp, Peter, Jampatong, Sansern, Chowchong, Surapol, Messmer, Rainer,
2011
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| Author(s): | Rupitak, Quanjai, Stamp, Peter, Jampatong, Sansern, Chowchong, Surapol, Messmer, Rainer |
| Title: | Temporal dynamics of kernel set of tropical sweet maize (Zea mays L.) as influenced by genotype and mild drought |
| Abstract: | Maize grain yield is often affected by drought stress at flowering. Fast and synchronous emergence of silks probably is the key to high kernel set but non-destructive methods to follow the temporal grain set were missing. We solved this problem by marking flint kernels on the ears of sweet maize to reflect daily kernel set, as modern sweet maize is quite similar in vigor to field maize in Thailand. The effects of mild pre-anthesis drought stress and of the genotype were examined in two experiments (over two years both). The highest number of kernels resulted from pollination on the first or second day of silking. More than 90% of the kernels per ear were usually set by day four or five. Mild drought stress reduced the number of kernel-bearing positions along the ear as well as the number of kernels per position on each day of pollination in 2007 but there was no significant deviation in the principal grain set curve. As a consequence of mild drought stress, the differences in daily kernel set between the two water regimes were rather small compared to the differences among genotypes, for which genotype-specific deviations from the general pattern of daily kernel set were observed. Most important, a new tool exists now to reliably study variable stress situations, using normal grains on sweet maize ears or yellow grains on white grain ears as visual marker systems. |
| Published in: | Maydica |
| Volume: | 56 |
| Issue: | 1 |
| Pages: | 25 - 31 |
| ISSN: | 0025-6153 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Bergamo |
| Publication status: | Published |
| Subjects: | Biologie allgemein|Biology, General, Landwirtschaft allgemein|Agriculture, General, Sweet maize, Flowering dynamics, Kernel set, Visual markers, Drought stress |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Sweet maize, Flowering dynamics, Kernel set, Visual markers, Drought stress |
| DBID source: | FORM-1318931780, WOS-000300601400005 |
| Nebis system number: | 003931813 |
Apoplastic pH and growth in expanding leaves of Vicia faba under salinity
,
Pitann, Britta, Kranz, Thorsten, Zörbb, Christian, Walter, Achim, Schurr, Ulrich, Mühling, Karl H.,
2011
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| Author(s): | Pitann, Britta, Kranz, Thorsten, Zörbb, Christian, Walter, Achim, Schurr, Ulrich, Mühling, Karl H. |
| Title: | Apoplastic pH and growth in expanding leaves of Vicia faba under salinity |
| Abstract: | Salinity affects water availability in the soil and subsequently the plant uptake capacity. Upon exposure to salt stress, leaf growth in monocot plants has been shown to be reduced instantaneously, followed by a gradual acclimation. The growth reactions are caused by an initial water deficit and an accompanied osmotic effect, followed by an IAA-induced sequestration of protons into the apoplast that increases leaf growth again as explained by the acid growth theory. In this study, we investigated the dynamics of growth reactions and apoplastic pH in leaves of the dicot Vicia faba in the presence of NaCl during the initiation of salt stress. Concurrent changes in apoplastic pH were detected by ratiometric fluorescence microscopy using the fluorescent dye fluorescein tetramethylrhodamine dextran. To elucidate the possible relation between the dynamics of leaf growth and apoplastic pH, results of the ratio imaging technique were combined with an in vivo growth analysis imaging approach. Leaf growth rate of V. faba was highest in the dusk and the early night phase; at this time a concomitant decrease of the apoplastic pH was observed. Under salinity, the apoplastic pH in leaves of V. faba increased with a simultaneous decrease of leaf growth towards increasing developmental stages, but with complex aberrations in the 24-h-leaf-growth pattern compared to control leaves. In conclusion, these results show that salt stress leads to an increase in apoplastic pH and to a declined leaf growth activity with complex 24-h-interactions of growth and pH in V. faba. |
| Published in: | Environmental and experimental botany |
| Volume: | 74 |
| Pages: | 31 - 36 |
| ISSN: | 0098-8472 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Apoplastic pH, Image analysis, Plant growth, Ratio imaging, Salinity, Vicia faba |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Apoplastic pH, Image analysis, Plant growth, Ratio imaging, Salinity, Vicia faba |
| DBID source: | FORM-1319465694 |
| DOI: | 10.1016/j.envexpbot.2011.04.015 |
| Nebis system number: | 000013717 |
Drought stress and tropical maize
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Messmer, Rainer, Fracheboud, Yvan, Bänziger, Marianne, Stamp, Peter, Ribaut, Jean-Marcel,
2011
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| Author(s): | Messmer, Rainer, Fracheboud, Yvan, Bänziger, Marianne, Stamp, Peter, Ribaut, Jean-Marcel |
| Title: | Drought stress and tropical maize |
| Subtitle: | QTLs for leaf greenness, plant senescence, and root capacitance |
| Abstract: | Genetically improved crops with higher water productivity help maintaining and increasing agricultural production in drought-prone areas. Their development involves, as in the case of maize, selection for high grain yield and improved secondary traits. With the objective of better understanding the role and regulation of the morphology of drought adaptation, a recombinant inbred line (RIL) population of tropical maize (Zea mays L.) was evaluated in six field experiments under intermediate (IS) and severe (SS) drought stress at flowering and under well-watered (WW) conditions in Mexico. The analyses per water regime revealed 32 quantitative trait loci (QTLs) for the five measurements of relative content of leaf chlorophyll (CL), 25 for the five visual ratings of plant senescence (SEN), and 11 for the three measurements of electric root capacitance (RCT). Impressive clusters of QTLs were observed on chromosomes 2 (bins 2.03-05), 4 (bin 4.09), and 10 (bins 10.04-05), suggesting that a small number of genes control chlorophyll metabolism and plant senescence. The high CL and low SEN of the drought resistant parent are aspects of its high water productivity resulting from improved constitutive traits. Co-locations of QTLs for CL, SEN and RCT with QTLs for plant height (PHT), the anthesis-silking interval (ASI), and grain yield (GY) were observed in bins 1.06-07, 8.06, and 4.09 but not for the large QTL clusters on chromosomes 2 and 10, suggesting independent genetic control of reproductive traits. Still, the phenotypic data showed that high CL and low SEN were favorable for grain yield production under drought, while delayed SEN was associated with higher grain yield under WW conditions. CL and SEN are suitable to complement selection for drought tolerance in order to sustain future breeding progress. |
| Published in: | Field crops research |
| Volume: | 124 |
| Issue: | 1 |
| Pages: | 93 - 103 |
| ISSN: | 0378-4290 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Maize, QTL, Drought stress, Leaf chlorophyll content, Senescence, Stay-green |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Maize, QTL, Drought stress, Leaf chlorophyll content, Senescence, Stay-green |
| DBID source: | FORM-1318931431, WOS-000296595800010 |
| DOI: | 10.1016/j.fcr.2011.06.010 |
| Nebis system number: | 000002745 |
A consensus map of QTLs controlling the root length of maize
,
Hund, Andreas, Reimer, Regina, Messmer, Rainer,
2011
>>
| Author(s): | Hund, Andreas, Reimer, Regina, Messmer, Rainer |
| Title: | A consensus map of QTLs controlling the root length of maize |
| Abstract: | Traits related to the root length of maize (Zea mays L.), reported by 15 QTL studies of nine mapping populations, were subjected to a QTL meta-analysis. Traits were grouped according to ontology, and we propose a system of abbreviations to unambiguously identify the different root types and branching orders. The nine maps were merged into a consensus map, and the number and positions of putative QTL clusters (MQTLs) were determined. A total of 161 QTLs was grouped into 24 MQTLs and 16 individual QTLs. Seven MQTLs harbored root traits, which had been reported to be collocated with QTLs for grain yield or other drought-responsive traits in the field. The most consistent collocations were observed for the number and weight of the seminal roots (five loci). Based on our analysis at least six loci are good candidates for further evaluation (bins 1.07, 2.04, 2.08, 3.06, 6.05 and 7.04). For example, the MQTL in bin 2.04 harbored ten different single QTLs; the MQTLs in bins 1.07 and 3.06 combined 11 and 7 QTLs, respectively, that were detected in more than three populations. The presented database is a first step for a comprehensive overview of the genetic architecture of root system architecture and its ecophysiological function. |
| Published in: | Plant and soil |
| Volume: | 344 |
| Issue: | 1-2 |
| Pages: | 143 - 158 |
| ISSN: | 0032-079X, 1573-5036 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Consensus map, Meta-analysis, QTL, Roots, Root system architecture, Zea mays L. |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Consensus map, Meta-analysis, QTL, Roots, Root system architecture, Zea mays L. |
| DBID source: | WOS-000291654600008 |
| DOI: | 10.1007/s11104-011-0735-9 |
| Nebis system number: | 000052447 |
UV-B Transmittance of Greenhouse Covering Materials Affects Growth and Flavonoid Content of Lettuce Seedlings
,
Walter, Achim, Behn, H., Tittmann, S., Schurr, U., Noga, G., Ulbrich, A.,
2010
>>
| Author(s): | Walter, Achim, Behn, H., Tittmann, S., Schurr, U., Noga, G., Ulbrich, A. |
| Title: | UV-B Transmittance of Greenhouse Covering Materials Affects Growth and Flavonoid Content of Lettuce Seedlings |
| Abstract: | In Europe, lettuce ( Lactuca sativa L., Asteraceae ) is commonly raised in greenhouses and transplanted to the field at the age of two to four weeks in order to prolong the growing season. The sudden exposure to outdoor conditions including altered temperature, radiation levels and rainfall events is extremely stressful for non-acclimated seedlings. Particularly the increase in ultraviolet-B radiation is considered a serious threat. A new approach to pre-acclimate seedlings to ambient ultraviolet-B radiation is the use of ultraviolet-B transparent covering materials. In order to estimate the benefit of UV-B pre-acclimation, lettuce plants were raised in greenhouses covered with three different materials varying in ultraviolet-B transmittance and transplanted to the field at the age of three weeks. Ultraviolet-B exposure during the greenhouse period led to a reduction in growth (leaf length, leaf area and leaf number) and an increase in flavonoid content. Transplantation to the field induced a strong enhancement in flavonoid content and a severe growth reduction overriding differences between UV-B treatment groups within a few days. At the time of harvest plant fresh weight was therefore independent from previous ultraviolet-B treatment. Effects of UV-B acclimation on plant performance immediately after transplantation require more detailed examination. |
| Published in: | European journal of horticultural science |
| Volume: | 75 |
| Issue: | 6 |
| Pages: | 259 - 268 |
| ISSN: | 1611-4426, 1611-4434 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Stuttgart |
| Publication status: | Published |
| Subjects: | Lactuca sativa, Biomass, Flavonoids, Leaf area, Leaf length, Lettuce, UV-B radiation |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Lactuca sativa, Biomass, Flavonoids, Leaf area, Leaf length, Lettuce, UV-B radiation |
| DBID source: | FORM-1319457405 |
| Nebis system number: | 004491026 |
Genetic variation in the gravitropic response of maize roots to low temperatures
,
Hund, Andreas,
2010
>>
| Author(s): | Hund, Andreas |
| Title: | Genetic variation in the gravitropic response of maize roots to low temperatures |
| Abstract: | The distribution of roots in soil determines their acquisition of spatially varying resources. It may be altered by changing the response of roots to gravity. The aim of the study was to assess gravitropic set-point angles (GSAs) of maize (Zea mays L.) roots, their response to temperature and the feasibility to measure them in growth pouches. The GSAs of the primary, seminal and crown roots of a set of nine temperate inbred lines were measured. The lines were grown under controlled conditions in growth columns either at 15/13°C or 24/20°C (day/night) until the two-leaf stage (V2). The GSA was measured as the deviation of the initial 3 cm of root axis from the vertical zero. Low temperature resulted in a decrease in the GSAs of the crown roots by 10°, i.e. the roots oriented more vertically. The effect of the GSAs on the distribution of the roots was verified in wider columns using two extreme inbred lines. The proportion of roots in the upper 5 cm of the columns was 78% for the line S335 with the strongest tendency to horizontal root growth and only 39% for CM105 with almost vertical orientation of the roots. The differences in GSAs between these two genotypes were even more pronounced in growth pouches, thus proving the feasibility of this system for rapid screening. The results indicate that there is a huge genetic variability available to alter the growth direction of the seedling roots of maize. However, there was little effect of the temperature. |
| Published in: | Plant root |
| Volume: | 4 |
| Pages: | 22 - 30 |
| ISSN: | 1881-6754 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Tokyo |
| Publication status: | Published |
| Subjects: | Corn, Gravitropism, Liminal angle, Plagio-gravitropism, Root angle, Zea mays L. |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Corn, Gravitropism, Liminal angle, Plagio-gravitropism, Root angle, Zea mays L. |
| DBID source: | FORM-1318491947 |
| DOI: | 10.3117/plantroot.4.22 |
UV-B Transmittance of Greenhouse Covering Materials Affects Growth and Flavonoid Content of Lettuce Seedlings
,
Achim Walter,
2010
>>
| Author(s): | Achim Walter |
| Title: | UV-B Transmittance of Greenhouse Covering Materials Affects Growth and Flavonoid Content of Lettuce Seedlings |
| Publication date / Date received: | 2010-01-01 |
| Language: | English |
| DBID source: | FORM-1319457643 |
Growth of axile and lateral roots of maize
,
Hund, A., Trachsel, S., Stamp, P.,
2009
>>
| Author(s): | Hund, A., Trachsel, S., Stamp, P. |
| Title: | Growth of axile and lateral roots of maize |
| Subtitle: | I development of a phenotying platform |
| Abstract: | The objective of this study was to develop a phenotyping platform for the non-destructive, digital measurement of early root growth of axile and lateral roots and to evaluate its suitability for identifying maize (Zea mays L.) genotypes with contrasting root development. The system was designed to capture images of the root system within minutes and to batch process them automatically. For system establishment, roots of the inbred line Ac7729/TZSRW were grown until nine days after germination on the surface of a blotting paper in pouches. An A4 scanner was used for image acquisition followed by digital image analysis. Image processing was optimized to enhance the separation between the roots and the background and to remove image noise. Based on the root length in diameter-class distribution (RLDD), small-diameter lateral roots and large-diameter axile roots were separated. Root systems were scanned daily to model the growth dynamics of these root types. While the axile roots exhibited an almost linear growth, total lateral root length increased exponentially. Given the determined exponential growth, it was demonstrated that two plants, germinated one day apart but with the same growth rates differed in root length by 100%. From the growth rates we were able to identify contrasting genotypes from 236 recombinant inbred lines (RILs) of the CML444 x SC-Malawi cross. Differences in the growth of lateral roots of two selected RILs were due to differences in the final length and linear density of the primary lateral roots, as proven by the manual reanalysis of the digital images. The high throughput makes the phenotyping platform attractive for routine genetic studies and other screening purposes. |
| Published in: | Plant and soil |
| Volume: | 325 |
| Issue: | 1-2 |
| Pages: | 335 - 349 |
| ISSN: | 0032-079X, 1573-5036 |
| Publication date / Date received: | 2009-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Digital image analysis, Corn, Early vigor, Root growth, Root morphology, Seedling vigor, Zea mays L |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Digital image analysis, Corn, Early vigor, Root growth, Root morphology, Seedling vigor, Zea mays L |
| DBID source: | PP-53737 |
| DOI: | 10.1007/s11104-009-9984-2 |
| Nebis system number: | 000052447 |
Group of Agronomy and Plant Breeding
Prof. Dr. Peter Stamp, emeritus.
Integration of Quality Protein in Waxy Maize by Means of Simple Sequence Repeat Markers
,
Sinkangam, Bunyarit, Stamp, Peter, Srinives, Peerasak, Jompuk, Peeranuch, Mongkol, Wassamon, Porniyom, Angkana, Dang, Ngoc-Chi, Jompuk, Choosak,
2011
>>
| Author(s): | Sinkangam, Bunyarit, Stamp, Peter, Srinives, Peerasak, Jompuk, Peeranuch, Mongkol, Wassamon, Porniyom, Angkana, Dang, Ngoc-Chi, Jompuk, Choosak |
| Title: | Integration of Quality Protein in Waxy Maize by Means of Simple Sequence Repeat Markers |
| Abstract: | Waxy, that is, pure, amylopectin maize (Zea mays L.) is an important staple food and vegetable in Southeast and East Asia. Its insufficient protein quality could be remedied by the opaque-2 gene mutation, demanding the combination of two recessive endosperm quality genes, opaque-2 (o(2)o(2)) and waxy (wxwx). Crosses were made between waxy and opaque-2 maize as female and male parents, respectively. In the segregating progenies of two crosses, Kwi1 x AgQ53 and Kwi9 x AgQ53, immediate selfing or one-time backcrossing to the waxy parent before selfing were used to achieve the combination o(2)o(2) wxwx, supported by marker-assisted selection (MAS) of opaque-2 by phi057 and of waxy by phi022. The final 11 o(2)o(2) wxwx lines were achieved both from initial backcrossing and selfing. All the o(2)o(2) wxwx lines were of acceptable agronomic vigor and had very high percentages of amylopectin. The sugar content was mostly higher in both selfing and backcrossing lines than in the parental waxy lines, an advantage for vegetable marketing. High lysine and tryptophan contents of the o(2)o(2) wxwx lines prove that the goal of combining two quality traits within one grain was achieved. Furthermore, high variation in grain quality traits is an incentive for further improvement by breeding. Consumption of high-quality protein maize will improve the diets of children, a good reason to produce double-quality vegetable waxy maize. |
| Published in: | Crop science |
| Volume: | 51 |
| Issue: | 6 |
| Pages: | 2499 - 2504 |
| ISSN: | 0011-183X |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Madison, WI |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | WOS-000295839200020 |
| DOI: | 10.2135/cropsci2011.05.0271 |
| Nebis system number: | 000036710 |
Root development, shoot growth and yields of maize as affected by irrigation schedules in a minor season in tropical Asia
,
Sangakkara, U.R., Amarasekera, P., Stamp, P.,
2011
>>
| Author(s): | Sangakkara, U.R., Amarasekera, P., Stamp, P. |
| Title: | Root development, shoot growth and yields of maize as affected by irrigation schedules in a minor season in tropical Asia |
| Abstract: | Maize is the most important upland cereal in tropical Asia, grown in both major and minor seasons under rainfed conditions. Due to the inadequate rainfall in the minor season, the crop is subjected to water stress, and irrigation helps to produce high yields. Smallholders who grow maize on flat beds in their allotments often use surface flood irrigation whenever irrigation water is available, which leads in most instances to inefficient use of this valuable resource. A field study was carried out over two minor seasons in Sri Lanka to determine the impact of different schedules of irrigation, developed on the basis of time intervals (3-, 7-, 14- or 21-day intervals or no irrigation as a control), which can easily be practised by smallholders, on the root development, shoot growth, seed yield and water use efficiency of maize. Irrigation at 3-day intervals produced fine roots in the top layers of the soil. Increasing the time interval between irrigation schedules to 7, 14 or 21 days reduced the percentage of fine roots, but developed more, heavier roots in the lower soil layers, as determined by root length densities (RLD) and root weight densities (RWD). Longer irrigation intervals or lack of irrigation resulted in a smaller number of heavier roots in the soil profile. The leaf water potential was affected to a greater degree than shoot water content or relative water content. The seed yield and harvest index were highest when maize was irrigated at 7-day intervals. In contrast, irrigation water use efficiency (IWUE) was highest at an irrigation interval of 14 days. The potential for optimizing water use in surface irrigation in flat beds while obtaining high yields in a tropical Asian minor season, when maize is subjected to moisture stress under smallholding conditions, is presented on the basis of this study. |
| Published in: | Acta Agronomica Hungarica |
| Volume: | 59 |
| Issue: | 2 |
| Pages: | 149 - 158 |
| ISSN: | 0238-0161, 1588-2527 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Budapest |
| Publication status: | Published |
| Subjects: | Maize, Irrigation, Root growth, Shoots, Water use efficiency, Yield |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Maize, Irrigation, Root growth, Shoots, Water use efficiency, Yield |
| DBID source: | FORM-1318930349 |
| DOI: | 10.1556/AAgr.59.2011.2.5 |
Growth, Yields, and Nitrogen-Use Efficiency of Maize (Zea mays L.) and Mungbean (Vigna radiata L. Wilczek) as Affected by Potassium Fertilizer in Tropical South Asia
,
Sangakkara, Ravi, Amarasekera, Prasanna, Stamp, Peter,
2011
>>
| Author(s): | Sangakkara, Ravi, Amarasekera, Prasanna, Stamp, Peter |
| Title: | Growth, Yields, and Nitrogen-Use Efficiency of Maize (Zea mays L.) and Mungbean (Vigna radiata L. Wilczek) as Affected by Potassium Fertilizer in Tropical South Asia |
| Abstract: | Application of chemical fertilizers in smallholder tropical farming systems of South Asia has become mandatory because of soil degradation, and nitrogen (N) is the most abundantly used nutrient. However, integrated management of N with potassium (K) could enhance productivity. Field studies tested the impact of fertilizer K on root development, seed yields, harvest indices, and N-use efficiencies of maize and mungbean, two popular smallholder crops over major and minor seasons. Application of 120 kg K ha-1 optimized all parameters of maize in the major wet season, whereas the requirement was 80 kg K ha-1 in the minor season. Optimal growth yields and N-use efficiencies of mungbean was with 80 kg K ha-1 in both seasons. Information regarding rates of fertilizer K that optimized N use and yield of maize and mungbean during each of the two tropical monsoonal seasons of South Asia is presented. |
| Published in: | Communications in soil science and plant analysis |
| Volume: | 42 |
| Issue: | 7 |
| Pages: | 832 - 843 |
| ISSN: | 0010-3624, 1532-2416 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Philadelphia, PA |
| Publication status: | Published |
| Subjects: | Landwirtschaft allgemein|Agriculture, General, Cropping seasons, maize, mungbean, nitrogen, potassium, tropics |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Cropping seasons, maize, mungbean, nitrogen, potassium, tropics |
| DBID source: | WOS-000288950000007 |
| DOI: | 10.1080/00103624.2011.552663 |
| Nebis system number: | 000036687 |
Temporal dynamics of kernel set of tropical sweet maize (Zea mays L.) as influenced by genotype and mild drought
,
Rupitak, Quanjai, Stamp, Peter, Jampatong, Sansern, Chowchong, Surapol, Messmer, Rainer,
2011
>>
| Author(s): | Rupitak, Quanjai, Stamp, Peter, Jampatong, Sansern, Chowchong, Surapol, Messmer, Rainer |
| Title: | Temporal dynamics of kernel set of tropical sweet maize (Zea mays L.) as influenced by genotype and mild drought |
| Abstract: | Maize grain yield is often affected by drought stress at flowering. Fast and synchronous emergence of silks probably is the key to high kernel set but non-destructive methods to follow the temporal grain set were missing. We solved this problem by marking flint kernels on the ears of sweet maize to reflect daily kernel set, as modern sweet maize is quite similar in vigor to field maize in Thailand. The effects of mild pre-anthesis drought stress and of the genotype were examined in two experiments (over two years both). The highest number of kernels resulted from pollination on the first or second day of silking. More than 90% of the kernels per ear were usually set by day four or five. Mild drought stress reduced the number of kernel-bearing positions along the ear as well as the number of kernels per position on each day of pollination in 2007 but there was no significant deviation in the principal grain set curve. As a consequence of mild drought stress, the differences in daily kernel set between the two water regimes were rather small compared to the differences among genotypes, for which genotype-specific deviations from the general pattern of daily kernel set were observed. Most important, a new tool exists now to reliably study variable stress situations, using normal grains on sweet maize ears or yellow grains on white grain ears as visual marker systems. |
| Published in: | Maydica |
| Volume: | 56 |
| Issue: | 1 |
| Pages: | 25 - 31 |
| ISSN: | 0025-6153 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Bergamo |
| Publication status: | Published |
| Subjects: | Biologie allgemein|Biology, General, Landwirtschaft allgemein|Agriculture, General, Sweet maize, Flowering dynamics, Kernel set, Visual markers, Drought stress |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Sweet maize, Flowering dynamics, Kernel set, Visual markers, Drought stress |
| DBID source: | FORM-1318931780, WOS-000300601400005 |
| Nebis system number: | 003931813 |
Drought stress and tropical maize
,
Messmer, Rainer, Fracheboud, Yvan, Bänziger, Marianne, Stamp, Peter, Ribaut, Jean-Marcel,
2011
>>
| Author(s): | Messmer, Rainer, Fracheboud, Yvan, Bänziger, Marianne, Stamp, Peter, Ribaut, Jean-Marcel |
| Title: | Drought stress and tropical maize |
| Subtitle: | QTLs for leaf greenness, plant senescence, and root capacitance |
| Abstract: | Genetically improved crops with higher water productivity help maintaining and increasing agricultural production in drought-prone areas. Their development involves, as in the case of maize, selection for high grain yield and improved secondary traits. With the objective of better understanding the role and regulation of the morphology of drought adaptation, a recombinant inbred line (RIL) population of tropical maize (Zea mays L.) was evaluated in six field experiments under intermediate (IS) and severe (SS) drought stress at flowering and under well-watered (WW) conditions in Mexico. The analyses per water regime revealed 32 quantitative trait loci (QTLs) for the five measurements of relative content of leaf chlorophyll (CL), 25 for the five visual ratings of plant senescence (SEN), and 11 for the three measurements of electric root capacitance (RCT). Impressive clusters of QTLs were observed on chromosomes 2 (bins 2.03-05), 4 (bin 4.09), and 10 (bins 10.04-05), suggesting that a small number of genes control chlorophyll metabolism and plant senescence. The high CL and low SEN of the drought resistant parent are aspects of its high water productivity resulting from improved constitutive traits. Co-locations of QTLs for CL, SEN and RCT with QTLs for plant height (PHT), the anthesis-silking interval (ASI), and grain yield (GY) were observed in bins 1.06-07, 8.06, and 4.09 but not for the large QTL clusters on chromosomes 2 and 10, suggesting independent genetic control of reproductive traits. Still, the phenotypic data showed that high CL and low SEN were favorable for grain yield production under drought, while delayed SEN was associated with higher grain yield under WW conditions. CL and SEN are suitable to complement selection for drought tolerance in order to sustain future breeding progress. |
| Published in: | Field crops research |
| Volume: | 124 |
| Issue: | 1 |
| Pages: | 93 - 103 |
| ISSN: | 0378-4290 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Maize, QTL, Drought stress, Leaf chlorophyll content, Senescence, Stay-green |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Maize, QTL, Drought stress, Leaf chlorophyll content, Senescence, Stay-green |
| DBID source: | FORM-1318931431, WOS-000296595800010 |
| DOI: | 10.1016/j.fcr.2011.06.010 |
| Nebis system number: | 000002745 |
QTL involved in the partial restoration of male fertility of C-type cytoplasmic male sterility in maize
,
Kohls, Susanne, Stamp, Peter, Knaak, Carsten, Messmer, Rainer,
2011
>>
| Author(s): | Kohls, Susanne, Stamp, Peter, Knaak, Carsten, Messmer, Rainer |
| Title: | QTL involved in the partial restoration of male fertility of C-type cytoplasmic male sterility in maize |
| Abstract: | Partial restoration of male fertility limits the use of C-type cytoplasmic male sterility (C-CMS) for the production of hybrid seeds in maize. Nevertheless, the genetic basis of the trait is still unknown. Therefore, the aim to this study was to identify genomic regions that govern partial restoration by means of a QTL analysis carried out in an F-2 population (n = 180). This population was derived from the Corn Belt inbred lines B37C and K55. F2BC1 progenies were phenotyped at three locations in Switzerland. Male fertility was rated according to the quality and number of anthers as well as the anthesis-silking interval. A weak effect of environment on the expression of partial restoration was reflected by high heritabilities of all fertility-related traits. Partial restoration was inherited like an oligogenic trait. Three major QTL regions were found consistently across environments in the chromosomal bins 2.09, 3.06 and 7.03. Therefore, a marker-assisted counter-selection of partial restoration is promising. Minor QTL regions were found on chromosomes 3, 4, 5, 6 and 8. A combination of partial restorer alleles at different QTL can lead to full restoration of fertility. The maternal parent was clearly involved in the partial restoration, because the restorer alleles at QTL in bins 2.09, 6.04 and 7.03 originated from B37. The three major QTL regions collocated with other restorer genes of maize, a phenomenon, which seems to be typical for restorer genes. Therefore, a study of the clusters of restorer genes in maize could lead to a better understanding of their evolution and function. In this respect, the long arm of chromosome 2 is particularly interesting, because it harbors restorer genes for the three major CMS systems (C, T and S) of maize. |
| Published in: | Theoretical and applied genetics |
| Volume: | 123 |
| Issue: | 2 |
| Pages: | 327 - 338 |
| ISSN: | 0040-5752, 1432-2242 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | WOS-000291600800011 |
| DOI: | 10.1007/s00122-011-1586-8 |
| Nebis system number: | 000985869 |
A consensus map of QTLs controlling the root length of maize
,
Hund, Andreas, Reimer, Regina, Messmer, Rainer,
2011
>>
| Author(s): | Hund, Andreas, Reimer, Regina, Messmer, Rainer |
| Title: | A consensus map of QTLs controlling the root length of maize |
| Abstract: | Traits related to the root length of maize (Zea mays L.), reported by 15 QTL studies of nine mapping populations, were subjected to a QTL meta-analysis. Traits were grouped according to ontology, and we propose a system of abbreviations to unambiguously identify the different root types and branching orders. The nine maps were merged into a consensus map, and the number and positions of putative QTL clusters (MQTLs) were determined. A total of 161 QTLs was grouped into 24 MQTLs and 16 individual QTLs. Seven MQTLs harbored root traits, which had been reported to be collocated with QTLs for grain yield or other drought-responsive traits in the field. The most consistent collocations were observed for the number and weight of the seminal roots (five loci). Based on our analysis at least six loci are good candidates for further evaluation (bins 1.07, 2.04, 2.08, 3.06, 6.05 and 7.04). For example, the MQTL in bin 2.04 harbored ten different single QTLs; the MQTLs in bins 1.07 and 3.06 combined 11 and 7 QTLs, respectively, that were detected in more than three populations. The presented database is a first step for a comprehensive overview of the genetic architecture of root system architecture and its ecophysiological function. |
| Published in: | Plant and soil |
| Volume: | 344 |
| Issue: | 1-2 |
| Pages: | 143 - 158 |
| ISSN: | 0032-079X, 1573-5036 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Consensus map, Meta-analysis, QTL, Roots, Root system architecture, Zea mays L. |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Consensus map, Meta-analysis, QTL, Roots, Root system architecture, Zea mays L. |
| DBID source: | WOS-000291654600008 |
| DOI: | 10.1007/s11104-011-0735-9 |
| Nebis system number: | 000052447 |
Impact of Green Manure on Productivity Patterns of Homegardens and Fields in a Tropical Dry Climate
,
Egodawatte, W.C.P., Sangakkara, U.R., Wijesinghe, D.B., Stamp, P.,
2011
>>
| Author(s): | Egodawatte, W.C.P., Sangakkara, U.R., Wijesinghe, D.B., Stamp, P. |
| Title: | Impact of Green Manure on Productivity Patterns of Homegardens and Fields in a Tropical Dry Climate |
| Abstract: | Extensive field farming and homegardening (representing an intensive resource management system) on different inclination positions were compared on the basis of soil quality and productivity of maize and Mung bean over two years, in Meegahakiula, Sri Lanka. Soil organic matter (SOM) content of homegardens was greater than in fields irrespective of the inclination and it was more pronounced in the flat category. After two years, SOM declined in both homegardens and fields, the depletion of SOM was greater in homegardens, due to a positive correlation between SOM depletion rate and crop yields. Green manures moderated SOM depletion. Mean maize yields in homegardens with recommended fertilizers (NPK) exceeded 5 Mg.ha-1 and was significantly different from Fields in both Flat and Moderate categories. No yield difference was observed in homegardens and Fields in the Steep category. Although mineral fertilizers had an overriding effect over green manures, plots without fertilizers (ZERO and G) had higher yields in homegardens. Mungbean yield was similar in homegardens and Fields with recommended fertilizers (NPK) in Flat category, in both years. However, the difference became significant with increasing inclination. The influence of green manure was overridden by the influence of mineral fertilizers while no difference was observed between homegardens and Fields without mineral fertilizers (ZERO). The study illustrated that homegardens as an intensive resource management system is more fertile and productive than the extensive field farming and more effective in terms of long term sustainability. |
| Published in: | Tropical agricultural research |
| Volume: | 22 |
| Issue: | 2 |
| Pages: | 172 - 182 |
| ISSN: | 1016-1422 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Peradeniya, Sri Lanka |
| Publication status: | Published |
| Subjects: | Green manure, Homegardens, Intensive resource management system, Sustainability |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Green manure, Homegardens, Intensive resource management system, Sustainability |
| DBID source: | FORM-1318930591 |
| DOI: | 10.4038/tar.v22i2.2826 |
| Nebis system number: | 004911578 |
Predicting seed admixture in maize combining flowering characteristics and a Lagrangian stochastic dispersion model
,
Dietiker, Dominique, Stamp, Peter, Eugster, Werner,
2011
>>
| Author(s): | Dietiker, Dominique, Stamp, Peter, Eugster, Werner |
| Title: | Predicting seed admixture in maize combining flowering characteristics and a Lagrangian stochastic dispersion model |
| Abstract: | The seed purity problem has received very low attention in maize coexistence studies, and has not been considered in prediction tools that simulate pollen flow and out-crossing between maize fields. To fill this gap we developed the Seed Admixture Model (SAMETH) able to predict seed admixture dispersion combining flowering characteristics (pollen shed, silks exertion) with a Lagrangian stochastic dispersion model. The model was tested with a dataset obtained from 20 fields in 2007 and in 2008, whose seeds were mixed with 1% of a homozygous blue-kernelled hybrid. The model was first calibrated with data from 6 fields and then validated with the data from the remaining 14 fields. Moreover, a sensitivity analysis was performed to test the consequences of different pollen quantities released by the admixture and the commercial hybrids. The measured seed admixture ranged from 0.7% to 6% and the model was able to simulate the seed admixture with r(2) = 0.83. The sensitivity analysis showed that the model was sensitive to the absolute released pollen quantities but it was still able to predict seed admixture rather accurately. Because of its reliability, the model could become a useful tool for case study scenarios that involve seed admixture and for which field implementations would be too complex and time-consuming. (C) 2010 Elsevier B.V. All rights reserved. |
| Published in: | Field crops research |
| Volume: | 121 |
| Issue: | 2 |
| Pages: | 256 - 267 |
| ISSN: | 0378-4290 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Seed purity, Admixture, Lagrangian stochastic model, Coexistence, Maize |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Seed purity, Admixture, Lagrangian stochastic model, Coexistence, Maize |
| DBID source: | WOS-000288473900007 |
| DOI: | 10.1016/j.fcr.2010.12.009 |
| Nebis system number: | 000002745 |
Field Simulation of Transgenic Seed Admixture Dispersion in Maize with a Blue Kernel Color Marker
,
Dietiker, Dominique, Oehen, Bernadette, Ochsenbein, Christian, Westgate, Mark E., Stamp, Peter,
2011
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| Author(s): | Dietiker, Dominique, Oehen, Bernadette, Ochsenbein, Christian, Westgate, Mark E., Stamp, Peter |
| Title: | Field Simulation of Transgenic Seed Admixture Dispersion in Maize with a Blue Kernel Color Marker |
| Abstract: | Seed purity in maize (Zea mays L.) has been almost neglected in coexistence studies. In this study, the impact of initial seed admixture was assessed in 20 fields (17 integrated pest management [IPM] and three organics) in the Swiss Midlands in 2007 and 2008 and a seed admixture threshold was proposed. The blue-kernelled French hybrid Adonis was used as a color-marker admixture. In 2009, its pollen production was assessed relative to those of two commercial hybrids (LG 32.12 and DKC 2960) that released 41 and 62%, respectively, less pollen than Adonis. Adonis was added to commercial yellow hybrid seeds at a proportion of 1:99. On average, the seed admixture at harvest was 2.8 times greater than the seed admixture at sowing. The greater pollen production of Adonis relative to yellow hybrids explained the increase in the harvest seed admixture via pollen flow. The lesser average kernel number per plant of Adonis (316 kernels plant−1; 451 kernels plant−1 for commercial hybrids) buffered the effect of pollen flow. Correcting for these differences provided simulation results compatible with the Hardy–Weinberg equilibrium for a trait with 1% frequency. When compared among the 20 field situations, (i) flower synchrony between admixture and commercial subpopulation and (ii) vertical distance between tassels of Adonis and ears of the commercial hybrid contributed most to field differences. To guarantee the 0.9% threshold imposed by the European Union for non-genetically-modified product, the seed admixture threshold should range between 0.2 and 0.5%. |
| Published in: | Crop science |
| Volume: | 51 |
| Issue: | 2 |
| Pages: | 829 - 837 |
| ISSN: | 0011-183X |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Madison, WI |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | FORM-1318928773 |
| DOI: | 10.2135/cropsci2010.06.0311 |
| Nebis system number: | 000036710 |
Composition of Starch and Protein in the Endosperm of Newly Generated Double Recessive Waxy and Opaque 2 Maize (Zea mays L.) Genotypes
,
Dang, N. C., Munsch, M., Aulinger I., Renlai, W., Le-Huy, H., Jampatong, S., Stamp, P.,
2011
>>
| Author(s): | Dang, N. C., Munsch, M., Aulinger I., Renlai, W., Le-Huy, H., Jampatong, S., Stamp, P. |
| Title: | Composition of Starch and Protein in the Endosperm of Newly Generated Double Recessive Waxy and Opaque 2 Maize (Zea mays L.) Genotypes |
| Abstract: | Waxy maize with its pure amylopectin starch is the staple food of many ethnic minorities in hilly regions of Southeast Asia (SEA). A combination of waxy and quality protein maize (QPM) traits would improve the quality of protein of waxy maize for human consumption. Double recessive waxy-QPM (wx-o2) genotypes had been generated from Southern Chinese material by haploid induction of crosses heterozygous for the two quality traits with an absolutely conserved waxy type and an improved amino acid profile. The vitreous kernel trait (due to the additional modifier genes present in QPM) was lost in the wx-o2 plant material; this may be due to the waxy mutation, this is anyhow desirable for acceptance as waxy maize is preferred due to its soft grains. The content of the quality limiting amino acid lysine was greatly increased in double recessive wx-o2 genotypes compared to standard waxy maize, but still with a high variation among genotypes for future improvement. Conclusively, it was indeed possible to combine two grain quality mutations successfully within one genotype and prototypes of double quality wx-o2 are available now to contribute to meet human requirements in essential amino acids and thus reduce malnutrition in various regions of Asia |
| Published in: | Journal of Agricultural Science and Technology |
| Volume: | 1 |
| Issue: | 5B |
| Pages: | 631 - 637 |
| ISSN: | 2161-6256, 2161-6264 |
| Publication date / Date received: | 2011-01-01 |
| Publication status: | Libertyville |
| Publication status: | Published |
| Subjects: | Quality protein maize, GBSS I granule-bound starch synthase I, waxy maize |
| Language: | English |
| Review status: | Peer Reviewed |
| Keyword: | Quality protein maize, GBSS I granule-bound starch synthase I, waxy maize |
| DBID source: | FORM-1321272551 |
Weather effects on cross-pollination in maize
,
Vogler, André, Bertossa, Mario, Aulinger-Leipner, Ingrid, Stamp, Peter,
2010
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| Author(s): | Vogler, André, Bertossa, Mario, Aulinger-Leipner, Ingrid, Stamp, Peter |
| Title: | Weather effects on cross-pollination in maize |
| Abstract: | Control of pollen dispersal is critical for the successful coexistence of genetically modified (GM) maize (Zea mays L.) and conventional maize. The impact of climate on cross-pollination by GM pollen was simulated in two field experiments with a color-recessive white-grain receptor DSP17007 and a color-dominant yellow-grain pollen donor in 2005 and 2006. The day after silk exertion of about 2500 marked single plants was taken as the basis for comparing weather data (maximum and minimum temperatures, relative humidity, wind speed, and average wind direction) with data on the cross-pollination of the white-grain receptor. Scattered significant correlations were found for all weather factors; only the minimum temperature at night had consistent negative correlations with rates of cross-pollination ranging from r = -0.22 to -0.45, indicating that the latter decreased as temperatures at night increased. In previous complementary field and growth chamber experiments, the grain set on one inbred line correlated significantly negatively with temperature up to 24 h before pollination (r = -0.55 to -0.66) because of pollen agglutination. This affects medium-distance pollen dispersals to a greater extent than short-distance ones; thus, cross-pollination with GM maize may be lower when the pollen donor has a proclivity for pollen agglutination at a high minimum temperature at night. |
| Published in: | Crop science |
| Volume: | 50 |
| Issue: | 2 |
| Pages: | 713 - 717 |
| ISSN: | 0011-183X |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Madison, WI |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | WOS-000275564500031 |
| DOI: | 10.2135/cropsci2009.04.0213 |
| Nebis system number: | 000036710 |
QTLs for early vigor of tropical maize
,
Trachsel, S., Messmer, R., Stamp, P., Ruta, N., Hund, A.,
2010
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| Author(s): | Trachsel, S., Messmer, R., Stamp, P., Ruta, N., Hund, A. |
| Title: | QTLs for early vigor of tropical maize |
| Abstract: | A strong photosynthetic performance and rapid leaf development, are important indicators of vigorous early growth. The aim of this study was to (1) evaluate the tropical maize (Zea mays L.) inbred lines CML444 and SC-Malawi for their photosynthetic performance at different growth stages and (2) assess quantitative trait loci (QTL) of photosynthesis-related traits in their 236 recombinant inbred lines at the heterotrophic growth stage. CML444 had a higher leaf chlorophyll (SPAD) content than SC-Malawi. Ten QTLs were found for the quantum efficiency of photosystem II (I broken vertical bar(PSII); four), SPAD (three) and the specific leaf area (SLA; three). The relevance of seedling QTLs for I broken vertical bar(PSII), SPAD and SLA for yield formation is emphasized by seven collocations (bins 5.01, 7.03, 8.05) with QTLs for kernel number and grain yield under field conditions. QTLs for SPAD at the V2 and at the reproductive stage did not collocate, indicating differences in the genetic control of SPAD at different growth stages. Knowing which loci affect SLA, SPAD and I broken vertical bar(PSII) simultaneously and which do not will help to optimize light harvest by the canopy. |
| Published in: | Molecular breeding |
| Volume: | 25 |
| Issue: | 1 |
| Pages: | 91 - 103 |
| ISSN: | 1380-3743, 1380-3743 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Wirtschaft, Recht und Politik allgemein|Economics, Law and Politics, General, QTL, Early vigor, Photosynthesis, Leaf chlorophyll content, SPAD, Zea mays L. |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | QTL, Early vigor, Photosynthesis, Leaf chlorophyll content, SPAD, Zea mays L. |
| DBID source: | WOS-000273034800007 |
| DOI: | 10.1007/s11032-009-9310-y |
| Nebis system number: | 001430119 |
Irrigation regimes affect early root development, shoot growth and yields of maize (Zea mays L.) in tropical minor seasons
,
Sangakkara, U.R., Amarasekera, P., Stamp, P.,
2010
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| Author(s): | Sangakkara, U.R., Amarasekera, P., Stamp, P. |
| Title: | Irrigation regimes affect early root development, shoot growth and yields of maize (Zea mays L.) in tropical minor seasons |
| Abstract: | Moisture stress is an important factor affecting field-grown maize in the tropics, especially in the minor dry seasons, and irrigation is required for successful crop growth and yields. Field experiments evaluated the impact of four irrigation regimes ranging from 3 to 21-day intervals on growth of maize (Zea mays L.) roots and shoots at critical stages and on seed yields when compared to those of irrigated maize plants in two minor seasons at Sri Lanka. While surface wetting at planting induced germination in all treatments, growth of seminal and first-order lateral roots was enhanced by increasing irrigation intervals. Relative water contents were similar at irrigation intervals of 3, 7 and 14 days and declined thereafter. At anthesis, root length and weight densities indicated the greater penetration into soil layers with increasing intervals of water supply. The highest yields were at 7 and 14-day irrigation intervals thus illustrating that regular water supply in minor dry seasons may be detrimental for maize growth and yields. |
| Published in: | Plant, soil and environment |
| Volume: | 56 |
| Issue: | 5 |
| Pages: | 228 - 234 |
| ISSN: | 1214-1178 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Prague |
| Publication status: | Published |
| Subjects: | Landwirtschaft allgemein|Agriculture, General, Umweltproblematik allgemein|Environmental Problems, General, maize, minor seasons, tropics, irrigation, root initiation, development, yields |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | maize, minor seasons, tropics, irrigation, root initiation, development, yields |
| DBID source: | WOS-000278035700004 |
| Nebis system number: | 004524506 |
Collocations of QTLs for Seedling Traits and Yield Components of Tropical Maize under Water Stress Conditions
,
Ruta, Nathinee, Stamp, Peter, Liedgens, Markus, Fracheboud, Yvan, Hund, Andreas,
2010
>>
| Author(s): | Ruta, Nathinee, Stamp, Peter, Liedgens, Markus, Fracheboud, Yvan, Hund, Andreas |
| Title: | Collocations of QTLs for Seedling Traits and Yield Components of Tropical Maize under Water Stress Conditions |
| Abstract: | Genetic variation in root morphology and its response to water deficit might be crucial for the adaptation of maize (Zea mays L.) to drought, but information about this is scarce. A set of 208 recombinant inbred lines (RILs) from the cross between Ac7643 (Parent 1) and Ac7729/TZSRW (Parent 2) was investigated in growth pouches to determine the traits of seedling roots and shoots. Water stress was induced by polyethylene glycol (PEG 8000). Quantitative trait loci (QTLs) were identified for seedling traits at the first leaf stage; their collocation was compared with published yield-related traits found in drought-stress experiments. Some seedling QTLs were specific to water stress, such as QTLs for root dry weight, shoot dry weight, and leaf area-to-root length ratio. Four root and shoot QTLs collocated in bin 2.02, indicating a relationship of this chromosome region to early vigor under water stress. Quantitative trait loci for ear number collocated with QTLs for the shoot-to-root dry weight ratio and leaf area-to-root length ratio Quantitative trait loci for the anthesis-silking interval collocated with QTLs for the numbers of crown roots and seminal roots irrespective of water supply. Quantitative trait loci controlling the balance between early root and shoot development may provide useful information to enable the prediction of maize performance under field conditions. |
| Published in: | Crop science |
| Volume: | 50 |
| Issue: | 4 |
| Pages: | 1385 - 1392 |
| ISSN: | 0011-183X |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Madison, WI |
| Publication status: | Published |
| Subjects: | Landwirtschaft allgemein|Agriculture, General |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | WOS-000279138200031 |
| DOI: | 10.2135/cropsci2009.01.0036 |
| Nebis system number: | 000036710 |
QTLs for the elongation of axile and lateral roots of maize in response to low water potential
,
Ruta, N., Liedgens, M., Fracheboud, Y., Stamp, Peter, Hund, A.,
2010
>>
| Author(s): | Ruta, N., Liedgens, M., Fracheboud, Y., Stamp, Peter, Hund, A. |
| Title: | QTLs for the elongation of axile and lateral roots of maize in response to low water potential |
| Abstract: | Changes in root architecture and the maintenance of root growth in drying soil are key traits for the adaptation of maize (Zea mays L.) to drought environments. The goal of this study was to map quantitative trait loci (QTLs) for root growth and its response to dehydration in a population of 208 recombinant inbred lines from the International Maize and Wheat Improvement Center (CIMMYT). The parents, Ac7643 and Ac7729/TZSRW, are known to be drought-tolerant and drought-sensitive, respectively. Roots were grown in pouches under well-watered conditions or at low water potential induced by the osmolyte polyethylene glycol (PEG 8000). Axile root length (L (Ax)) increased linearly, while lateral root length (L (Lat)) increased exponentially over time. Thirteen QTLs were identified for six seedling traits: elongation rates of axile roots (ERAx), the rate constant of lateral root elongation (k (Lat)), the final respective lengths (L (Ax) and L (Lat)), and the ratios k (Lat)/ERAx and L (Lat)/L (Ax.) While QTLs for lateral root traits were constitutively expressed, most QTLs for axile root traits responded to water stress. For axile roots, common QTLs existed for ERAx and L (Ax). Quantitative trait loci for the elongation rates of axile roots responded more clearly to water stress compared to root length. Two major QTLs were detected: a QTL for general vigor in bin 2.02, affecting most of the traits, and a QTL for the constitutive increase in k (Lat) and k (Lat)/ERAx in bins 6.04-6.05. The latter co-located with a major QTL for the anthesis-silking interval (ASI) reported in published field experiments, suggesting an involvement of root morphology in drought tolerance. Rapid seedling tests are feasible for elucidating the genetic response of root growth to low water potential. Some loci may even have pleiotropic effects on yield-related traits under drought stress. |
| Published in: | Theoretical and applied genetics |
| Volume: | 120 |
| Issue: | 3 |
| Pages: | 621 - 631 |
| ISSN: | 0040-5752, 1432-2242 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Biologie allgemein|Biology, General, Drought, QTL, Root growth, Water potential, Drought resistance, Zea mays L., Corn |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Drought, QTL, Root growth, Water potential, Drought resistance, Zea mays L., Corn |
| DBID source: | WOS-000273755200011 |
| DOI: | 10.1007/s00122-009-1180-5 |
| Nebis system number: | 000985869 |
The temporal dynamics of kernel set in tropical sweet maize determined by visual markers
,
Rupitak, Quanjai, Stamp, Peter, Jampatong, Sansern, Chowchong, Surapol, Messmer, Rainer,
2010
>>
| Author(s): | Rupitak, Quanjai, Stamp, Peter, Jampatong, Sansern, Chowchong, Surapol, Messmer, Rainer |
| Title: | The temporal dynamics of kernel set in tropical sweet maize determined by visual markers |
| Abstract: | The initiation of kernels along the maize ear depends on the temporal dynamics of silk emergence and pollen shedding. We conducted a nondestructive examination of the dynamics of silk emergence of tropical sweet maize (Zea mays L.); flint-type grains were the visual markers. The silks were pollinated on consecutive days with pollen of sweet maize (recessive allele) on 6 d and with pollen of flint-type maize (dominant allele) on 1 d (one pollination treatment for each of the seven possible days). The resulting hard kernels could be distinguished from the shriveled sweet kernels. The time of pollination had a strong effect on kernel set. The highest percentage of daily kernel set was observed on the first day of silking (Day 1). It accounted for 31 (2007) and 42% (2008) of the total kernels per ear. The distribution of these kernels followed a bell-shaped curve with a peak at around the position of the tenth kernel from the bottom of the ear. On the following days, kernel set followed a double bell-shaped curve with the peak shifting to the tip of the ear followed by a steady decrease. The minor peak, at the bottom of the ears, almost disappeared by Day 4 of silking. More than 90% of the final number of kernels was set within five (2007) or three (2008) days. The visual marker system successfully traced the dynamics of silk emergence and its impact on kernel set as well as its dependence on environmental conditions during flowering. |
| Published in: | Crop science |
| Volume: | 50 |
| Issue: | 6 |
| Pages: | 2499 - 2505 |
| ISSN: | 0011-183X |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Madison, WI |
| Publication status: | Published |
| Subjects: | Landwirtschaft allgemein|Agriculture, General |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | FORM-1291803228, WOS-000284134000032 |
| DOI: | 10.2135/cropsci2010.04.0196 |
| Nebis system number: | 000036710 |
Early Growth of Crotalaria (Crotalaria juncea), Tithonia (Tithonia diversifolia), and Maize (Zea mays) as Affected by Soil Fertility and Phosphorus Fertilizer under Pot and Field Conditions
,
Rast, Helen, Liedgens, Markus, Sangakkara, U.R., Stamp, Peter,
2010
>>
| Author(s): | Rast, Helen, Liedgens, Markus, Sangakkara, U.R., Stamp, Peter |
| Title: | Early Growth of Crotalaria (Crotalaria juncea), Tithonia (Tithonia diversifolia), and Maize (Zea mays) as Affected by Soil Fertility and Phosphorus Fertilizer under Pot and Field Conditions |
| Abstract: | Green manures are important in tropical cropping systems and are planted in degraded soils, thus affecting early growth. Pot and field experiments evaluated the impact of soil fertility on early growth of two important tropical green manures (Crotalaria juncea and Tithonia diversifolia) when compared to that of maize (Zea mays) with high and low levels of phosphorus fertilizer. Growth of tithonia was not affected by soil fertility level irrespective of phosphorus fertilizer, indicating its suitability for degraded soils. Crotalaria was affected by soil fertility (root growth was stimulated by phosphorus), indicating its potential for soils with some degree of fertility. Maize was significantly affected by soil fertility and phosphorus fertilizers, indicating the requirement of fertile soils for the successful development of a good root and shoot system. The importance of field studies in the tropics is also presented as the diverse field conditions reduces significant effects found in pot studies. |
| Published in: | Communications in soil science and plant analysis |
| Volume: | 41 |
| Issue: | 14 |
| Pages: | 1655 - 1664 |
| ISSN: | 0010-3624, 1532-2416 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Philadelphia, PA |
| Publication status: | Published |
| Subjects: | Early growth, green manure crops, maize, phosphorus fertilizer, soil fertility |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Early growth, green manure crops, maize, phosphorus fertilizer, soil fertility |
| DBID source: | FORM-1291813970 |
| DOI: | 10.1080/00103624.2010.488710 |
| Nebis system number: | 000036687 |
Subsoil Root Growth of Field Grown Spring Wheat Genotypes (Triticum Aestivum L.) Differing in Nitrogen Use Efficiency Parameters
,
Noulas, Christos, Liedgens, Markus, Stamp, Peter, Alexiou, Ioannis, Herrera, Juan M.,
2010
>>
| Author(s): | Noulas, Christos, Liedgens, Markus, Stamp, Peter, Alexiou, Ioannis, Herrera, Juan M. |
| Title: | Subsoil Root Growth of Field Grown Spring Wheat Genotypes (Triticum Aestivum L.) Differing in Nitrogen Use Efficiency Parameters |
| Abstract: | In a two-year (1999-2000) field experiment four Swiss spring wheat (Triticum aestivum L.) genotypes (cvs. 'Albis', 'Toronit' and 'Pizol' and an experimental line 'L94491') were compared for genotypic differences in the root parameters that determine uptake potential and nitrogen use efficiency (NUE):root surface area (RSA) and its components, root length density (RLD) and the diameter of the roots. The genotypes were grown under no (N0) and under ample fertilizer nitrogen (N) [ammonium nitrate (NH4NO3); N1; 250 kg N ha-1] supply. Root samples were taken from all the genotypes at anthesis from the subsoil (30-60 cm). Genotypic effects on RLD and RSA were evident only in 2000 and large amounts of N fertilizer usually diminished root growth. Adequate soil moisture in 1999 may have favored the establishment of the root system of all the genotypes before anthesis. Parameters of NUE for each genotype were also determined at anthesis and at physiological maturity. 'Albis' the least efficient cv. in recovering fertilizer N (ranged from 36.5 to 61.1%) with the lowest N uptake efficiency (0.47 to 0.79 kg kg-1) had the lowest RLD and RSA in both seasons. Among genotypes 'Toronit', a high-yielding cv., efficient in recovering fertilizer N, exhibited the higher NUE (22.4 to 29.3 kg kg-1) and tended to have the highest values of RLD and RSA. Nitrogen fertilization also led to an increase in the proportion of roots with diameters less than 300 m and decreased the proportion of roots with diameters of 300 to 700 m. These trends were more pronounced for cv. 'Pizol' in 1999 and for cv. 'Toronit' in 1999 and 2000. By anthesis in a humid temperate climate, there are no marked differences in the subsoil root growth of the examined genotypes. Some peculiarities on the root growth characteristics of the cultivars 'Albis' and 'Toronit' may partially explain their different NUE performance. |
| Published in: | Journal of plant nutrition |
| Volume: | 33 |
| Issue: | 13 |
| Pages: | 1887 - 1903 |
| ISSN: | 0190-4167, 1532-4087 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | London, UK |
| Publication status: | Published |
| Subjects: | Wheat, Root length density, Root surface area, Root diameter classes, Nitrogen use efficiency parameters |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Wheat, Root length density, Root surface area, Root diameter classes, Nitrogen use efficiency parameters |
| DBID source: | WOS-000281903100001 |
| DOI: | 10.1080/01904167.2010.512049 |
| Nebis system number: | 000006331 |
Grain Yield Increase and Pollen Containment by Plus-Hybrids Could Improve Acceptance of Transgenic Maize
,
Munsch, Magali A., Stamp, Peter, Christov, Nikolai K., Foueillassar, Xavier M., Huesken, Alexandra, Camp, Karl-Heinz, Weider, Christophe,
2010
>>
| Author(s): | Munsch, Magali A., Stamp, Peter, Christov, Nikolai K., Foueillassar, Xavier M., Huesken, Alexandra, Camp, Karl-Heinz, Weider, Christophe |
| Title: | Grain Yield Increase and Pollen Containment by Plus-Hybrids Could Improve Acceptance of Transgenic Maize |
| Abstract: | Maize (Zea mays L.) Plus-Hybrids are a blend of cytoplasmic male-sterile (CMS) hybrids and unrelated male-fertile hybrids ensuring pollination of the whole stand. Combining potential benefits of male sterility (CMS effect) and allo-pollination (xenia effect), they often outperform the corresponding male-fertile sib-pollinated hybrids in terms of yield. The combining abilities of five CMS hybrids and eight pollinators were investigated in a factorial split-plot design in 12 environments in four countries and two years. The plant material from different breeders represented the three types of male-sterile cytoplasm. Plus-Hybrids increased grain yield, on average, by 10% or more and by up to 20% in specific environments. Three highly responsive CMS hybrids and four generally good pollinators were identified. The Plus-Hybrid effect affected both yield components, CMS leading mainly to a higher number of kernels (KN) and the xenia effect mainly to an increase in the thousand kernel weight (TKW). Despite some differences in the response of the three types of CMS, the effect of the cytoplasm was not significant. While the CMS effect depended strongly on environment, the xenia was consistent in all environments but its extent varied. As well as increasing yield, we can expect that Plus-Hybrids can make a large contribution to the coexistence of transgenic and conventional maize by biocontainment, that is eliminating or reducing the release of transgenic pollen in Bacillus thuringiensis (Bt) maize or herbicide-tolerant (HT) maize. |
| Published in: | Crop science |
| Volume: | 50 |
| Issue: | 3 |
| Pages: | 909 - 919 |
| ISSN: | 0011-183X |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Madison, WI |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | WOS-000276961900019 |
| DOI: | 10.2135/cropsci2009.03.0117 |
| Nebis system number: | 000036710 |
Genetic variation in root architecture of maize and its response to abiotic stresses
,
Hund, Andreas,
2010
>>
| Author(s): | Hund, Andreas |
| Title: | Genetic variation in root architecture of maize and its response to abiotic stresses |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Zürich |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | FORM-1294243734 |
Root Growth and Nitrate-Nitrogen Leaching of Catch Crops following Spring Wheat
,
Herrera, Juan M., Feil, Boy, Stamp, Peter, Liedgens, Markus,
2010
>>
| Author(s): | Herrera, Juan M., Feil, Boy, Stamp, Peter, Liedgens, Markus |
| Title: | Root Growth and Nitrate-Nitrogen Leaching of Catch Crops following Spring Wheat |
| Abstract: | Growing nitrogen (N) catch crops can reduce NO3-N leaching after cultivating cereals The objective of this study was to relate NO3-N leaching to variation in the uptake of N and the size and distribution of the root systems of different catch crops species. In a 3-yr lysimeter experiment, phacelia (Phacelia tanacetifolia Benth), sunflower (Helianthus annuns L), and a Brassica species (yellow mustard [Brassica alba L] or a hybrid of turnip rape [B rape L spp. oleifera (DC) Metzg] and Chinese cabbage [B rape L ssp chinensis (L) Hanelt]) were grown after the harvest of spring wheat under two levels of N supply. Bare soil lysimeters served as the control. Water percolation from the lysimeters and the NO3- concentration in the leachate were measured weekly from the sowing until the presumed frost-kill of the catch crops Minirhizotrons were used to assess the spatial and temporal patterns of root growth from 0 10 to 1 00 m The catch crop species differed in their shoot biomass, N uptake. total NO3-N leaching, and root growth The results suggested that diet e was no strict relationship between the total NO3-N leaching of each catch crop species and the N uptake or parameters that indicate static characteristics of the root system In contrast. the ranking of each catch crop species by parameters that indicate early root growth was inversely related to the ranking of each catch crop species in NO3-N leaching The rapid establishment of the root system is essential for a catch crop following spring wheat to reduce the amount of NO3-N leaching after the harvest of spring wheat. |
| Published in: | Journal of environmental quality |
| Volume: | 39 |
| Issue: | 3 |
| Pages: | 845 - 854 |
| ISSN: | 0047-2425, 1537-2537 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Madison, WI |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | WOS-000277129100009 |
| DOI: | 10.2134/jeq2009.0306 |
| Nebis system number: | 000013890 |
A minirhizotron imaging system to identify roots expressing the green fluorescent protein
,
Faget, Marc, Liedgens, Markus, Stamp, Peter, Fluetsch, Patrick, Herrera, Juan Manuel,
2010
>>
| Author(s): | Faget, Marc, Liedgens, Markus, Stamp, Peter, Fluetsch, Patrick, Herrera, Juan Manuel |
| Title: | A minirhizotron imaging system to identify roots expressing the green fluorescent protein |
| Abstract: | The limited flexibility available in the configuration of commercial minirhizotron imaging systems makes it difficult to adapt these systems to new applications. It is also too expensive to introduce modifications, which are often very temporary to these systems at the end of the development process. In order to identify the roots of a single species in mixed plant stands, we developed a new minirhizotron imaging system that makes it possible to observe roots expressing green fluorescent protein (GFP). This system is based on affordable and easily obtainable components such as webcams. Here, we report a protocol to identify suitable webcams for constructing a minirhizotron imaging system and demonstrate the application of this protocol to build a minirhizotron imaging system that can identify the roots of a transformed maize plant expressing GFP. |
| Published in: | Computers and electronics in agriculture |
| Volume: | 74 |
| Issue: | 1 |
| Pages: | 163 - 167 |
| ISSN: | 0168-1699 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Roots, Minirhizotron, Webcam, Imaging, Green fluorescent protein |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Roots, Minirhizotron, Webcam, Imaging, Green fluorescent protein |
| DBID source: | WOS-000283271800017 |
| DOI: | 10.1016/j.compag.2010.06.010 |
| Nebis system number: | 000031772 |
Genetic structure and history of Swiss maize (Zea mays L. ssp mays) landraces
,
Eschholz, T. W., Stamp, P., Peter, R., Leipner, J., Hund, A.,
2010
>>
| Author(s): | Eschholz, T. W., Stamp, P., Peter, R., Leipner, J., Hund, A. |
| Title: | Genetic structure and history of Swiss maize (Zea mays L. ssp mays) landraces |
| Abstract: | Between 1930 and 2003 with emphasis on the 1940s maize landraces (Zea mays L. ssp. mays) from all over Switzerland were collected for maintenance and further use in a new Swiss breeding program. The genetic relationship and diversity among these accessions stored in the Swiss gene bank is largely unknown. Our hypothesis was that due to the unique geographic, climatic, and cultural diversity in Switzerland a diverse population of maize landraces had developed over the past three centuries. The aims were to characterize the genetic diversity of the Swiss landraces and their genetic relationship with accessions from neighbouring regions as well as reviewing their history, collection, and maintenance. The characterization and grouping was based on analyses with ten microsatellite markers. Geographic, cultural, and climatic conditions explained a division in two distinct groups of accessions. One group consisted of landraces collected in the southern parts of Switzerland. This group was related to the Italian Orange Flints. The other group contained accessions from northern Switzerland which were related to Northern European Flints in particular German Flints. Historic evidence was found for a frequent exchange of landraces within the country resulting in a lack of region-specific or landrace-specific genetic groups. The relatively large separation between the accessions, indicated by high F (ST) (0.42), might be explained partly by a bottleneck during the collection and maintenance phase as well as by geographical and cultural separation of north and south of the country. Due to the high genetic diversity, the accessions here are a potential resource for broadening the European flint pool. |
| Published in: | Genetic resources and crop evolution |
| Volume: | 57 |
| Issue: | 1 |
| Pages: | 71 - 84 |
| ISSN: | 0925-9864, 1573-5109 |
| Publication date / Date received: | 2010-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Corn/maize, Flint, Germplasm collection, History, Landrace, Open pollinated variety, Rheintaler, Zea mays |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Corn/maize, Flint, Germplasm collection, History, Landrace, Open pollinated variety, Rheintaler, Zea mays |
| DBID source: | WOS-000273809800007 |
| DOI: | 10.1007/s10722-009-9452-0 |
| Nebis system number: | 000695663 |
Impact of topography on cross-pollination in maize (Zea mays L.)
,
Vogler, André, Eisenbeiss, Henri, Aulinger-Leipner, Ingrid, Stamp, Peter,
2009
>>
| Author(s): | Vogler, André, Eisenbeiss, Henri, Aulinger-Leipner, Ingrid, Stamp, Peter |
| Title: | Impact of topography on cross-pollination in maize (Zea mays L.) |
| Abstract: | Understanding cross-pollination is important to achieve the coexistence of genetically modified (GM) and conventional maize (Zea mays L.); it is still not known whether topography favors or hinders cross-pollination. In 2005 and 2006, the effect of gradients of 3.4–6.8° on cross-pollination was investigated in the canton of Zurich, Switzerland. Cross-pollination was revealed by the presence of yellow-grains on a white-grain hybrid at distances up to 17.5 m from the yellow-grain pollen donor hybrid. The measurements of the inclination of the slope were based on aerial images data taken by an unmanned GPS/INS (Global Positioning System/Inertial Navigation System)-based and stabilized model helicopter, which delivered precise altitude-based data for sampling points at tassel height. The rate of cross-pollination increased significantly with decreasing altitude of the receptor field (r = 0.36–0.64). However, the effect seems to be weaker than that of other factors like wind direction and velocity. |
| Published in: | European journal of agronomy |
| Volume: | 31 |
| Issue: | 2 |
| Pages: | 99 - 102 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2009-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Landwirtschaft allgemein|Agriculture, General, Cross-pollination, Maize, Inclination, Topography, Coexistence, GIS, Unmanned aerial vehicle, Photogrammetry |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Cross-pollination, Maize, Inclination, Topography, Coexistence, GIS, Unmanned aerial vehicle, Photogrammetry |
| DBID source: | PP-51343, PP-53762 |
| DOI: | 10.1016/j.eja.2009.04.003 |
| Nebis system number: | 000650747 |
Mapping of QTLs for lateral and axile root growth of tropical maize
,
Trachsel, Samuel, Messmer, Rainer, Stamp, Peter, Hund, Andreas,
2009
>>
| Author(s): | Trachsel, Samuel, Messmer, Rainer, Stamp, Peter, Hund, Andreas |
| Title: | Mapping of QTLs for lateral and axile root growth of tropical maize |
| Abstract: | Maize genotypes may adapt to dry environments by avoiding desiccation by means of a deeper root system or by maintaining growth and water extraction at low water potentials. The aim of this study was to determine the quantitative genetic control of root growth and root morphology in a population of 236 recombinant inbred lines (RILs) from the cross between CML444 (high-yielding) × SC-Malawi (low-yielding), which segregates for the response to drought stress at flowering. The RILs and the parental lines were grown on blotting paper in growth pouches until the two-leaf stage under non-stressed conditions; the parents were additionally exposed to desiccation stress induced by polyethylene glycol with a molecular weight of 8000 Dalton (PEG-8000). The lengths of axile and lateral roots were measured non-destructively at 2, 5, 7 and 9 days after germination, by scanning with an A4 scanner followed by digital image analysis. CML444 had a lower rate constant of lateral root elongation (kLat) than SC-Malawi, but the two genotypes did not differ in their response to desiccation. QTLs affecting root vigor, as depicted by increments in kLat, the elongation rate of axile roots (ERAx) and the number of axile roots (NoAx) were identified in bins 2.04 and 2.05. QTLs for NoAx and ERAx collocated with QTLs for yield parameters in bins 1.03–1.04 and 7.03–04. The correspondence of QTLs for axile root traits in bins 1.02–1.03 and 1.08 and QTLs for lateral roots traits in bins 2.04–2.07 in several mapping populations suggests the presence of genes controlling root growth in a wide range of genetic backgrounds. |
| Published in: | Theoretical and applied genetics |
| Volume: | 119 |
| Issue: | 8 |
| Pages: | 1413 - 1424 |
| ISSN: | 0040-5752, 1432-2242 |
| Publication date / Date received: | 2009-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Biologie allgemein|Biology, General |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | PP-53760 |
| DOI: | 10.1007/s00122-009-1144-9 |
| Nebis system number: | 000985869 |
Peter Stamp
,
Roux, Michel,
2009
>>
| Author(s): | Roux, Michel |
| Title: | Peter Stamp |
| Subtitle: | Wir setzen alles daran, das gentische Potential der grossen Kulturpflanzen voll auszuschöpfen |
| Abstract: | Seit 21 Jahren forscht und lehrt Peter Stamp als Professor für Agronomie und Pflanzenzüchtung an der ETH Zürich. Im Januar 2011 wird er emeritiert. Er sieht die Schweiz als Vorbild für einen produktiven und nachhaltigen Pflanzenbau. Peter Stamp fait de la recherche et de 'enseignement depuis 21 ans en tant que professeur d'agronomie et de sélection végétale � l'EPF Zurich. En janvier 2011 il prendra sa retraite. Deux de ses souhaits pour le futur: La recherche végétale doit tout mettre en oeuvre afin de tirer le maximum du potentiel génétique des principales plantes cultivées. Faute de quoi, il ne sera pas possible d'atteindre l'objectif fixé actuellement que est de doubler la production végétale d'ici 2050. Pour ce faire, les plantes devront cependant être mieux adaptées qu'aujourd'hui aux systèmes agro-écologiques et aux types de climat correspondants. Ceci est une lourde tâche. Deuxième souhait: L'EPF Zurich forme d'excellents spécialistes en production végétale, avec une renommée internationale. Cependant, ils ne sont pas assez nombreux. Il en faudra nettement plus. |
| Published in: | Journal : Ingenieure ETH Agrar, Lebensmittel, Umwelt |
| Issue: | 43/44 |
| Pages: | 4 - 6 |
| Publication date / Date received: | 2009-01-01 |
| Publication status: | Zollikofen |
| Publication status: | Published |
| Language: | German |
| Review status: | Internally reviewed |
| DBID source: | PP-54571, PP-56597 |
| Nebis system number: | 002044612 |
Chilling stress in maize
,
Leipner, Jörg,
2009
>>
| Author(s): | Leipner, Jörg |
| Title: | Chilling stress in maize |
| Subtitle: | From physiology to genetics and molecular mechanisms |
| Publication date / Date received: | 2009-01-01 |
| Publication status: | Zurich |
| Publication status: | Published |
| Subjects: | Acker- und Futterbau (inkl. Kultur- und Nutzpflanzen) | Crop and Fodder Farming (incl. Cultivated and Crop Plants), Botanik |Botany |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | FORM-1294243858 |
| DOI: | 10.3929/ethz-a-005794605 |
Rooting depth and water use efficiency of tropical maize inbred lines, differing in drought tolerance
,
Hund, Andreas, Ruta, Nathinee, Liedgens, Markus,
2009
>>
| Author(s): | Hund, Andreas, Ruta, Nathinee, Liedgens, Markus |
| Title: | Rooting depth and water use efficiency of tropical maize inbred lines, differing in drought tolerance |
| Abstract: | Deep rooting has been identified as strategy for desiccation avoidance in natural vegetation as well as in crops like rice and sorghum. The objectives of this study were to determine root morphology and water uptake of four inbred lines of tropical maize (Zea mays L.) differing in their adaptation to drought. The specific questions were i) if drought tolerance was related to the vertical distribution of the roots, ii) whether root distribution was adaptive or constitutive, and iii) whether it affected water extraction, water status, and water use efficiency (WUE) of the plant. In the main experiment, seedlings were grown to the V5 stage in growth columns (0.80 m high) under well-watered (WW) and water-stressed (WS) conditions. The depth above which 95 % of all roots were located (D95) was used to estimate rooting depth. It was generally greater for CML444 and Ac7729/TZSRW (P2) compared to SC-Malawi and Ac7643 (P1). The latter had more lateral roots, mainly in the upper part of the soil column. The increase in D95 was accompanied by increases in transpiration, shoot dry weight, stomatal conductance and relative water content without adverse effects on the WUE. Differences in the morphology were confirmed in the V8 stage in large boxes: CML444 with thicker (0.14 mm) and longer (0.32 m) crown roots compared to SC-Malawi. Deep rooting, drought sensitive P2 showed markedly reduced WUE, likely due to an inefficient photosynthesis. The data suggest that a combination of high WUE and sufficient water acquisition by a deep root system can increase drought tolerance. |
| Published in: | Plant and soil |
| Volume: | 318 |
| Issue: | 1-2 |
| Pages: | 311 - 325 |
| ISSN: | 0032-079X, 1573-5036 |
| Publication date / Date received: | 2009-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Drought avoidance, Root length density, Root morphology, Stomatal conductance, Water use efficiency, Zea mays L |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Drought avoidance, Root length density, Root morphology, Stomatal conductance, Water use efficiency, Zea mays L |
| DBID source: | PP-53735 |
| DOI: | 10.1007/s11104-008-9843-6 |
| Nebis system number: | 000052447 |
The use of green fluorescent protein as a tool to identify roots in mixed plant stands
,
Faget, Marc, Herrera, Juan M., Stamp, Peter, Aulinger-Leipner, Ingrid, Frossard, Emmanuel, Liedgens, Markus,
2009
>>
| Author(s): | Faget, Marc, Herrera, Juan M., Stamp, Peter, Aulinger-Leipner, Ingrid, Frossard, Emmanuel, Liedgens, Markus |
| Title: | The use of green fluorescent protein as a tool to identify roots in mixed plant stands |
| Abstract: | Roots take up most of the resources required by a plant, but a lack of efficient research tools hinders our understanding of the function and relevance of the root system. This is especially evident when the research focus is not on a single plant, but on multiple plants that share the same soil resources. None of the available methods allow for simple, inexpensive, non-destructive, and objective assignment of observed roots in a mixture of plants to a target plant. Here, we demonstrate that transgenic plants expressing the green fluorescent protein (GFP), combined with the well established minirhizotron technique, is a route to overcoming this limitation. We planted transgenic maize (Zea mays L.) in combination with either its corresponding wild type, Italian ryegrass (Lolium multiflorum Lam.), or soybean (Glycine max (L.) Merr.). Identification of fluorescent roots allows the relative distribution of roots of each plant type and their interaction and interference with each other to be observed. The selected plants are suitable for model experiments to unravel fundamental belowground ecological processes. Because genetic transformation of plants is an established technique that can be applied to a large set of plant species, this method will be of interest to a broad range of research areas. |
| Published in: | Functional plant biology |
| Volume: | 36 |
| Issue: | 10-11 |
| Pages: | 930 - 937 |
| ISSN: | 1445-4408 |
| Publication date / Date received: | 2009-01-01 |
| Publication status: | Collingwood |
| Publication status: | Published |
| Subjects: | imaging system, minirhizotron, root research methodology, root interactions |
| Event name: | 1st International Plant Phenomics Symposium (IPPS 2009) |
| Event date: | April 21-24, 2009 |
| Place: | Canberra, Australia |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | imaging system, minirhizotron, root research methodology, root interactions |
| DBID source: | PP-51215, PP-53731 |
| DOI: | 10.1071/FP09125 |
| Nebis system number: | 004240289 |
Effect of tillage systems and herbicides on the control of Yellow Nutsedge (Cyperus esculentus L.) in maize
,
Waldispühl, S., Stamp, P., Streit, B.,
2008
>>
| Author(s): | Waldispühl, S., Stamp, P., Streit, B. |
| Title: | Effect of tillage systems and herbicides on the control of Yellow Nutsedge (Cyperus esculentus L.) in maize |
| Published in: | Journal of plant diseases and protection |
| Issue: | Sp. Iss. 21 |
| Pages: | 509 - 514 |
| ISSN: | 1861-3829, 0340-8159, 1861-3837 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Stuttgart |
| Publication status: | Published |
| Event name: | 24th German Conference on Weed Biology and Weed Control |
| Event date: | March 4-6, 2008 |
| Place: | Stuttgart-Hohenheim, Germany |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | PP-42061 |
| Nebis system number: | 000039466 |
Impact of improved fallow periods on soil properties and productivity of maize (Zea mays L.) in major and minor seasons of Asian humid tropics
,
Sangakkara, U. R., Stamp, Peter,
2008
>>
| Author(s): | Sangakkara, U. R., Stamp, Peter |
| Title: | Impact of improved fallow periods on soil properties and productivity of maize (Zea mays L.) in major and minor seasons of Asian humid tropics |
| Abstract: | Improved fallows are considered an easy, low cost and suitable method of increasing the productivity and sustainability of smallholder tropical rainfed cropping systems, although most farmers allow weeds to grow when the environmental conditions are not conductive for crop production. Field studies were carried out over the minor and major seasons, to evaluate the impact of a preceding improved fallow using Crotalaria or Tithonia , two popular tropical green manures, on selected soil properties, and on the growth and yield of maize. Improved fallows enhanced chemical soil properties significantly and the impact was most prominent at the onset of the minor maize season. Thus, the growth and yield of maize was also increased to a greater extent in this season, when yields are generally lower due to the suboptimal climatic conditions of lower rainfall and higher temperatures. However, fallows in the minor season also improved soil characteristics and maize yields in the major season, the most significant impact being increased seed yields and harvest indices. Although farmers may not grow fallow crops in major seasons, the potential of these green manure fallows in increasing maize yields in minor seasons and possible strategies to include the fallows in the cropping sequences of tropical rainfed upland cropping systems are discussed on the basis of this field study. |
| Published in: | Acta Agronomica Hungarica |
| Volume: | 56 |
| Issue: | 3 |
| Pages: | 303 - 312 |
| ISSN: | 0001-513X, 0238-0161 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Budapest |
| Publication status: | Published |
| Subjects: | improved fallows, soil improvement, maize yields, humid tropics |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | improved fallows, soil improvement, maize yields, humid tropics |
| DBID source: | PP-42058 |
| DOI: | 10.1556/AAgr.56.2008.3.6 |
| Nebis system number: | 000041500 |
Effects of organic matter and time of incorporation on root development of tropical maize seedlings
,
Sangakkara, U. R., Nissanka, S. P., Stamp, P.,
2008
>>
| Author(s): | Sangakkara, U. R., Nissanka, S. P., Stamp, P. |
| Title: | Effects of organic matter and time of incorporation on root development of tropical maize seedlings |
| Abstract: | Smallholders in the tropics add different organic materials to their crops at different times, based on the availability of materials and labour. However, the time of application could have an effect on the establishment and early growth of crops, especially their root systems, which has not yet been clearly identified. This paper presents the results of a study conducted under greenhouse conditions using soils from a field treated with three organic materials at 4 or 2 weeks before or at the planting of maize seeds, corresponding to the times that tropical smallholders apply these materials. The organic materials used were leaves of Gliricidia sepium and Tithonia diversifolia or rice straw, incorporated at a rate equivalent to 6 Mt ha −1 . A control treatment where no organic matter was added was used for comparison. The impact of the treatments on soil properties at the planting of maize seed and detailed root analysis based on root lengths were carried out until the last growth stage (V4). The addition of organic matter improved the soil characteristics, and the impact of adding Gliricidia leaves was most pronounced when incorporated 2 weeks before planting. The benefits of leaves of Tithonia or rice straw on soil quality parameters were clearly evident when added 4 weeks before planting. Organic matter enhanced the root number, root length, root growth rate and branching indices. All the organic materials suppressed the growth of maize roots when applied at planting, suggesting the existence of allelopathic effects, which could result in poor growth. The most benefits in terms of root growth were observed with Tithonia. |
| Published in: | Acta Agronomica Hungarica |
| Volume: | 56 |
| Issue: | 2 |
| Pages: | 169 - 178 |
| ISSN: | 0238-0161, 1588-2527 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Budapest |
| Publication status: | Published |
| Subjects: | maize, organic matter, time of application, root growth |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | maize, organic matter, time of application, root growth |
| DBID source: | PP-42059 |
| DOI: | 10.1556/AAgr.56.2008.2.6 |
Impact of locally derived organic materials and method of addition on maize yields and nitrogen use efficiencies in major and minor seasons of tropical South Asia
,
Sangakkara, Ravi, Attanayake, K. B., Stamp, Peter,
2008
>>
| Author(s): | Sangakkara, Ravi, Attanayake, K. B., Stamp, Peter |
| Title: | Impact of locally derived organic materials and method of addition on maize yields and nitrogen use efficiencies in major and minor seasons of tropical South Asia |
| Abstract: | Maize is the most important highland cereal grown in the tropics, generally cultivated under rainfed smallholder conditions in Asia. Field experiments were carried out in Sri Lanka with the objective of determining the impact of three types of organic matter applied as mulch or incorporated on the yields and nitrogen uptake by maize cultivated under rainfed conditions in the South Asian major and minor seasons. The organic matter used was leaves of Gliricidia sepium, Tithonia diversifolia, or rice straw, with the full compliment of recommended mineral fertilizers. Organic matter, especially the two green manures, enhanced yields and nitrogen (N) uptake of maize, and the impact was more prominent in the minor dry season where the yields were lower. Incorporation of organic matter had a greater positive impact in the dry season in terms of N utilization efficiency and seed yields. The beneficial impact of organic matter with low carbon (C):N ratios in enhancing N nutrition and seed yields of rainfed maize in major and more importantly in the minor seasons is presented. |
| Published in: | Communications in Soil Science and Plant Analysis |
| Volume: | 39 |
| Issue: | 17/18 |
| Pages: | 2584 - 2596 |
| ISSN: | 0010-3624, 1532-2416 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Philadelphia, PA |
| Publication status: | Published |
| Subjects: | Maize, nitrogen use efficiency, organic matter, seed yields, tropical seasons |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Maize, nitrogen use efficiency, organic matter, seed yields, tropical seasons |
| DBID source: | PP-42060 |
| DOI: | 10.1080/00103620802358623 |
| Nebis system number: | 000036687 |
Growth, yield, and yield components of winter wheat and the effects of tillage intensity, preceding crops, and N fertilisation
,
Rieger, S., Richner, W., Streit, B., Frossard, E., Liedgens, M.,
2008
>>
| Author(s): | Rieger, S., Richner, W., Streit, B., Frossard, E., Liedgens, M. |
| Title: | Growth, yield, and yield components of winter wheat and the effects of tillage intensity, preceding crops, and N fertilisation |
| Abstract: | Conservation tillage is widely practiced in semi-arid climates, mostly in small grain crop rotations. It is implemented to a much lesser extent in cool and humid climates of Europe, mainly due to a lack of knowledge about agronomic and ecological impacts. This study was conducted in light- to medium-textured soils in the Swiss midlands from 1995 to 2000. The aim was to determine whether tillage intensity impacted wheat yield and measure the effects of the preceding crop and the level of N fertilisation. Conventional tillage (CT) with ploughing, minimum tillage (MT) with a chisel, and no-tillage (NT) were studied in the following crop rotation: winter wheat (Triticum aestivum L.)–oilseed rape (Brassica napus L.)–winter wheat–maize (Zea mays L.). Winter wheat was grown at either 0 kg N ha−1 (N0) or at the recommended N supply (N1). Harvest residues of all the crops were left on the field. In the early stages wheat development under NT was slightly slower than under CT and MT, but at maturity the shoot biomass was 2% higher under NT than under the other tillages. The grain yield decreased by 3% under NT compared to CT and MT, mainly due to fewer ears per area and a significantly lower thousand-kernel weight. Wheat planted after oilseed rape had significantly higher shoot biomass and grain yield than wheat planted after maize. At the beginning of the vegetation season there were small but significant differences in the soil mineral N content among the tillage treatments. Accordingly, the level of N fertiliser applied was adjusted to ensure similar N availability in all tillage systems. The relative reduction in grain yield under NT compared to CT and MT was similar with and without N fertilisation. Thus, N availability was not a limiting factor for the yield of NT wheat in this study. |
| Published in: | European journal of agronomy |
| Volume: | 28 |
| Issue: | 3 |
| Pages: | 405 - 411 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Winter wheat, Tillage intensity, Yield, Crop rotation |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Winter wheat, Tillage intensity, Yield, Crop rotation |
| DBID source: | PP-42057 |
| DOI: | 10.1016/j.eja.2007.11.006 |
| Nebis system number: | 000650747 |
Response of the photosynthetic apparatus of cotton (Gossypium hirsutum) to the onset of drought stress under field conditions studied by gas-exchange analysis and chlorophyll fluorescence imaging
,
Massacci, A., Nabiev, S.M., Pietrosanti, L., Nematov, S.K., Chernikova, T.N., Thor, K., Leipner, J.,
2008
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| Author(s): | Massacci, A., Nabiev, S.M., Pietrosanti, L., Nematov, S.K., Chernikova, T.N., Thor, K., Leipner, J. |
| Title: | Response of the photosynthetic apparatus of cotton (Gossypium hirsutum) to the onset of drought stress under field conditions studied by gas-exchange analysis and chlorophyll fluorescence imaging |
| Abstract: | The functioning of the photosynthetic apparatus of cotton (Gossypium hirsutum) grown during the onset of water limitation was studied by gas-exchange and chlorophyll fluorescence to better understand the adaptation mechanisms of the photosynthetic apparatus to drought conditions. For this, cotton was grown in the field in Central Asia under well-irrigated and moderately drought-stressed conditions. The light and CO2 responses of photosynthesis (AG), stomatal conductance (gs) and various chlorophyll fluorescence parameters were determined simultaneously. Furthermore, chlorophyll fluorescence images were taken from leaves to study the spatial pattern of photosystem II (PSII) efficiency and non-photochemical quenching parameters. Under low and moderate light intensity, the onset of drought stress caused an increase in the operating quantum efficiency of PSII photochemistry (PSII) which indicated increased photorespiration since photosynthesis was hardly affected by water limitation. The increase in PSII was caused by an increase of the efficiency of open PSII reaction centers (Fv′/Fm′) and by a decrease of the basal non-photochemical quenching (NO). Using a chlorophyll fluorescence imaging system a low spatial heterogeneity of PSII was revealed under both irrigation treatments. The increased rate of photorespiration in plants during the onset of drought stress can be seen as an acclimation process to avoid an over-excitation of PSII under more severe drought conditions. |
| Published in: | Plant physiology and biochemistry |
| Volume: | 46 |
| Issue: | 2 |
| Pages: | 189 - 195 |
| ISSN: | 0981-9428 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Paris |
| Publication status: | Published |
| Subjects: | Chlorophyll fluorescence imaging, Drought acclimation, Gossypium hirsutum, Photorespiration, Photosynthesis, Stomatal conductance |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Chlorophyll fluorescence imaging, Drought acclimation, Gossypium hirsutum, Photorespiration, Photosynthesis, Stomatal conductance |
| DBID source: | PP-37006 |
| DOI: | 10.1016/j.plaphy.2007.10.006 |
| Nebis system number: | 000037518 |
QTL studies reveal little relevance of chilling-related seedling traits for yield in maize
,
Leipner, Jörg, Jompuk, Choosak, Camp, Karl-Heinz, Stamp, Peter, Fracheboud, Yvan,
2008
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| Author(s): | Leipner, Jörg, Jompuk, Choosak, Camp, Karl-Heinz, Stamp, Peter, Fracheboud, Yvan |
| Title: | QTL studies reveal little relevance of chilling-related seedling traits for yield in maize |
| Abstract: | Prolonged low temperature phases and short-term cold spells often occur in spring during the crucial stages of early maize (Zea mays L.) development. The effect of low temperature-induced growth retardation at the seedling stage on final yield is poorly studied. Therefore, the aim was to identify genomic regions associated with morpho-physiological traits at flowering and harvest stage and their relationship to previously identified quantitative trait loci (QTLs) for photosynthesis and morpho-physiological traits from the same plants at seedling stage. Flowering time, plant height and shoot biomass components at harvest were measured in a dent mapping population for cold tolerance studies, which was sown in the Swiss Midlands in early and late spring in two consecutive years. Early-sown plants exhibited chilling stress during seedling stage, whereas late-sown plants grew under favorable conditions. Significant QTLs, which were stable across environments, were found for plant height and for the time of flowering. The QTLs for flowering were frequently co-localized with QTLs for plant height or ear dry weight. The comparison with QTLs detected at seedling stage revealed only few common QTLs. A pleiotropic effect was found on chromosome 3 which revealed that a good photosynthetic performance of the seedling under warm conditions had a beneficial effect on plant height and partially on biomass at harvest. However, a high chilling tolerance of the seedling seemingly had an insignificant or small negative effect on the yield. |
| Published in: | Theoretical and Applied Genetics |
| Volume: | 116 |
| Issue: | 4 |
| Pages: | 555 - 562 |
| ISSN: | 0040-5752, 1432-2242 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | PP-42056 |
| DOI: | 10.1007/s00122-007-0690-2 |
| Nebis system number: | 000985869 |
Eine Vision für den Schweizer Pflanzenbau im Jahr 2050
,
Kölliker, Roland, Gaume, Alain, Hund, Andreas, Winzeler, Michael, Einsele, Arthur,
2008
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| Author(s): | Kölliker, Roland, Gaume, Alain, Hund, Andreas, Winzeler, Michael, Einsele, Arthur |
| Title: | Eine Vision für den Schweizer Pflanzenbau im Jahr 2050 |
| Abstract: | 2050 werden die Rahmenbedingungen für den Pflanzenbau in der Schweiz nicht wieder zu erkennen sein. Hauptursachen dafür sind globale und freie Märkte mit stärkerem Wettbewerbsdruck, der Klimawandel mit häufigeren Extremereignissen sowie die knapper werdenden Ressourcen: Die Bodenqualität verschlechtert sich, das ackerfähige Land schwindet und Wasser wird nicht mehr jeder Zeit frei verfügbar sein. Ist unter diesen Umständen ein produktiver Pflanzenbau in der Schweiz überhaupt noch möglich und sinnvoll? Was braucht es um einen zukunftsfähigen Pflanzenbau zu ermöglichen? Diese Fragen stellten sich Expertinnen und Experten unter der Leitung der Schweizerischen Gesellschaft für Pflanzenbauwissenschaften (SGPW) im Projekt Vision Pflanzenbau 2050. Die Studie kommt zum Schluss, dass nur auf der Basis von wissenschaftlichen und technologischen Neuerungen im Pflanzenbau die Landwirtschaft auch im Jahr 2050 noch genügend qualitativ hochwertige Nahrungsmittel produzieren kann. Eng damit gekoppelt sind die Erhaltung der Produktionsflächen sowie der notwendigen gesellschaftlichen Güter wie Landschaft zur Erholung, gesicherte Trinkwasserversorgung oder der Erhalt der Biodiversität. Die SGPW zeigt den aktuellen Forschungs- und Entwicklungsbedarf auf, um einen qualitativ und quantitativ hochstehenden Pflanzenbau für die Zukunft zu ermöglichen. En 2050, les conditions cadre pour la production végétale ne seront plus reconnaissables. Les raisons principales en sont les marchés globalisés et libéralisés avec une pression concurrentielle plus forte, les changements climatiques avec des événements extrêmes plus fréquents ainsi que la raréfaction des ressources: la qualité du sol se détériore, les terrains destinés aux grandes cultures se réduisent encore d’avantage et l’approvisionnement en eau est toujours plus incertain. Dans ces conditions, une production végétale en Suisse est-elle encore imaginable? Comment permettre le développement d’une production végétale porteuse d’avenir? Des experts de la production végétale se sont posé ces questions sous la direction de la Société suisse d’agronomie (SSA) dans le cadre du projet « Vision production végétale 2050 ». Cette étude a permis de mettre en évidence que seule l’innovation scientifique et technologique dans le domaine de la production végétale peut permettre à l’agriculture d’assurer, même en 2050, les prestations nécessaires à une alimentation de qualité en quantités suffisantes. Et en même temps de supporter la préservation des ressources naturelles telles que l’eau potable, la biodiversité et des paysages attrayants. La SSA révèle les besoins actuels en terme de recherche et de développement, afin de maintenir à long terme une production végétale de qualité en quantités suffisantes. The basic conditions for plant production in Switzerland will have substantially changed by 2050. The main reasons are global and free markets with increased competition, climate change causing more frequently occurring disasters and scarcity of resources: soil quality will diminish, arable land will disappear and water will no longer be constantly available. Is plant production in Switzerland still feasible and expedient under these circumstances? What are the requirements for plant production in the future? Experts in plant sciences addressed these questions during the project “Perspectives for Plant Production 2050” of the Swiss Society of Agronomy (SSA). The conclusions of the study were, that the production of sufficient foods of high quality is only possible based on scientific and technological progress in plant sciences and production. In addition, conservation of fertile agricultural land and public commodities such as recreational landscapes, secure supply of drinking water and conservation of biodiversity are a necessity. The SSA highlights the requirements for research and development for enabling a plant production of high quality and quantity in the future. |
| Published in: | AgrarForschung |
| Volume: | 15 |
| Issue: | 7 |
| Pages: | 332 - 337 |
| ISSN: | 1022-663X |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Bern |
| Publication status: | Published |
| Subjects: | plant production, 2050, perspectives, climate change, scarcity of resources, changed basic conditions |
| Language: | German |
| Review status: | Peer reviewed |
| Keyword: | plant production, 2050, perspectives, climate change, scarcity of resources, changed basic conditions |
| DBID source: | PP-42055 |
| Nebis system number: | 000926925 |
Cold tolerance of maize seedlings as determined by root morphology and photosynthetic traits
,
Hund, Andreas, Fracheboud, Yvan, Soldati, Alberto, Stamp, Peter,
2008
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| Author(s): | Hund, Andreas, Fracheboud, Yvan, Soldati, Alberto, Stamp, Peter |
| Title: | Cold tolerance of maize seedlings as determined by root morphology and photosynthetic traits |
| Abstract: | Mild chilling stress and slow soil warming are common causes for a retarded early development of maize (Zea mays L.). The objective of this study was to evaluate cold tolerance of a divers set of 14 inbred lines with respect to root morphology as well as the function of the photosynthetic apparatus. Plants were grown until the 2-leaf stage under growth chamber conditions at air and soil temperatures of 15/13 °C and 24/20 °C (day/night). Four contrasting genotypes were tested at 15/13 °C and 17/13 °C (day/night) in the topsoil simulating temperature differences as occurring in no-tillage in comparison with conventional tillage systems. The small variation in the day temperature of 15 °C versus 17 °C in the topsoil affected plant growth and a significant genotype-by-temperature interaction was detected for the chlorophyll content (SPAD) and the operating efficiency of photosystem II (ΦPSII). At 15/13 °C compared to 24/20 °C, differences between genotypes for the primary lateral root (PrLat) length and its portion on the embryonic root system were hardly affected by temperature. ΦPSII and the lateral root length were closest related to plant dry weight at 15/13 °C (r2 = 0.56 and 0.75, respectively), the axile root length and the leaf area were closest related to plant dry weight at 24/20 °C (r2 = 0.46 and 0.83, respectively). Therefore, the selection for long PrLat roots holds promise for the improvement of early vigour in environments and cropping systems with reduced soil warming in spring but might be disadvantageous under warmer conditions. |
| Published in: | European Journal of Agronomy |
| Volume: | 28 |
| Issue: | 3 |
| Pages: | 178 - 185 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Chlorophyll content, Chlorophyll fluorescence, Cold tolerance, Corn, Chilling, Root morphology, Primary root, Seminal root, Soil temperature, Zea mays |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Chlorophyll content, Chlorophyll fluorescence, Cold tolerance, Corn, Chilling, Root morphology, Primary root, Seminal root, Soil temperature, Zea mays |
| DBID source: | PP-42054 |
| DOI: | 10.1016/j.eja.2007.07.003 |
| Nebis system number: | 000650747 |
Performance of winter wheat varieties in white clover living mulch
,
Hiltbrunner, Jürg, Liedgens, Markus,
2008
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| Author(s): | Hiltbrunner, Jürg, Liedgens, Markus |
| Title: | Performance of winter wheat varieties in white clover living mulch |
| Published in: | Biological agriculture & horticulture : BAH : an international journal for sustainable production systems |
| Issue: | 26 |
| Pages: | 85 - 101 |
| ISSN: | 0144-8765 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Berkhamsted |
| Publication status: | Published |
| Language: | English |
| Review status: | Peer reviewed |
| DBID source: | PP-42053 |
| Nebis system number: | 000017328 |
Proteomic analysis of wheat recombinant inbred lines: Variations in prolamin and dough rheology.
,
Gobaa, Samy, Bancel, Emmanuelle, Branlard, Gérard, Kleijer, Geert, Stamp, Peter,
2008
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| Author(s): | Gobaa, Samy, Bancel, Emmanuelle, Branlard, Gérard, Kleijer, Geert, Stamp, Peter |
| Title: | Proteomic analysis of wheat recombinant inbred lines: Variations in prolamin and dough rheology. |
| Abstract: | To investigate the impact of the 1BL.1RS translocation on dough strength and to understand how 1BL.1RS genotypes may overcome the loss of Glu-B3 and Gli-B1, proteomic profiles of 16 doubled haploid (DH) lines of similar glutenin composition but of different strength, as measured by Chopin's alveograph, were compared. The results showed that 32 spots, mainly prolamins, were differentially expressed and that five others were specific to high-strength DH lines. The identification and quantification of the prolamin fractions on the two-dimensional (2D) electrophoresis gels demonstrated that the high-molecular weight glutenin sub-unit (HMW-GS) were up-regulated by 25% in 1BL.1RS DH lines, even though the corresponding genes were not located on the missing 1BS chromosome. The γ-gliadins were also up-regulated (by 36%) in such lines to counterbalance, to some extent, the loss of LMW-GS of Glu-B3. The polymeric prolamin fractions also accumulated in high-tenacity lines and decreased in high-extensibility lines confirming the role of the inter-chain disulfide bonds in resistance to deformation. In contrast, the monomeric fraction of α-gliadin favored extensibility and decreased tenacity by increasing the accumulation (+12%) of α-gliadins in high-extensibility lines; the Gli-A1 allele of the parent Toronit was found to be more abundant when compared to the Gli-A1 allele of parent 211.12014. |
| Published in: | Journal of Cereal Science |
| Volume: | 47 |
| Issue: | 3 |
| Pages: | 610 - 619 |
| ISSN: | 0733-5210 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Wheat, Proteome, Prolamins, Alveograph, Bread-making quality |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Wheat, Proteome, Prolamins, Alveograph, Bread-making quality |
| DBID source: | PP-42052 |
| DOI: | 10.1016/j.jcs.2007.07.001 |
| Nebis system number: | 000021083 |
Genetic diversity of Swiss maize (Zea mays L. ssp. mays) assessed with individuals and bulks on agarose gels
,
Eschholz, Tobias W., Peter, Roland, Stamp, Peter, Hund, Andreas,
2008
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| Author(s): | Eschholz, Tobias W., Peter, Roland, Stamp, Peter, Hund, Andreas |
| Title: | Genetic diversity of Swiss maize (Zea mays L. ssp. mays) assessed with individuals and bulks on agarose gels |
| Abstract: | About 65 years ago, more than 150 Swiss maize landraces (Zea mays L. ssp. mays) of the flint type were collected and conserved ex situ. Due to the climatically and culturally diverse environment of the Alps, a considerable genetic diversity of this material was assumed. To prove this, an efficient method was required to carry out genetic profiling of all the accessions in the Swiss Gene Bank. Simple sequence repeat marker (SSR) profiling in combination with the visualization of the polymerase chain reaction (PCR) products on agarose gels was chosen. Here a set of 19 different landrace accessions was analyzed to: (i) investigate their genetic diversity, (ii) investigate and display the population structure and (iii) determine whether DNA bulks rather than single plants can be used for such analyses. Four repeated samples of one accession were found to be much closer to one another than to the rest of accessions. Furthermore, specific alleles were identified for several accessions. The PCR products of the bulked DNA samples represented only a small part of the variation revealed by the analysis of individuals. Loci with four base repeat motifs performed better in the analysis of bulks than loci with other repeat motifs. The correlation between genetic distance matrices, based on the analysis of individuals and bulks, respectively, was significant. Thus, the single plant approach allowed for sufficient differentiation of accessions, and DNA bulks visualized on agarose gels led to correlated genetic distances although a limited number of alleles were detected. Although the limited resolution of agarose gels likely causes some bias, profiling of larger sets with the individual plant approach appears feasible and more informative compared to the bulk analysis we conducted. |
| Published in: | Genetic resources and crop evolution |
| Volume: | 55 |
| Issue: | 7 |
| Pages: | 971 - 983 |
| ISSN: | 0925-9864, 1573-5109 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Agarose gels, Bulk analysis, Genetic distance, Flint maize (Zea mays L. ssp. mays), Landraces, SSR profiling |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Agarose gels, Bulk analysis, Genetic distance, Flint maize (Zea mays L. ssp. mays), Landraces, SSR profiling |
| DBID source: | PP-42051 |
| DOI: | 10.1007/s10722-007-9304-8 |
| Nebis system number: | 000695663 |
Short-distance cross-pollination of maize in a small-field landscape as monitored by grain color markers
,
Bannert, Michael, Vogler, André, Stamp, Peter,
2008
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| Author(s): | Bannert, Michael, Vogler, André, Stamp, Peter |
| Title: | Short-distance cross-pollination of maize in a small-field landscape as monitored by grain color markers |
| Abstract: | Results of studies on cross-pollination in small field environments with regard to donor/receptor surface ratios and flower synchrony are scarce. In 2003 and 2004, six field experiments on cross-pollination were carried out in the cantons of Zug and Zurich, two hilly regions of Switzerland. Three (Monopol, Romario and PR39G12) color-dominant yellow-grain maize varieties (Zea mays L.) were planted in close proximity (0.8 m) to color-recessive white-grain maize (DSP17007). The factors of influence were size of the donor and receptor parts of the field and flower synchrony, tested in a tight grid pattern (2.4 m × 10 m; 6000 ears ha−1). Widely varying field size ratios of donors to receptors (about 4:1–1:8) did not influence the cross-pollination rate at distances of 0–20 m from the pollen donor. The synchrony between pollen shedding of the donor and silking of the receptor had a large impact on cross-pollination. In relation to the mid-phase of silk emergence in the receptor field, a temporal isolation of five and seven days resulted in a significant decrease in cross-pollination by more than 80% in comparison to full synchrony. However, in a receptor field with irregular emergence of a number of weak, late-flowering plants led to a remarkable increase in cross-pollination, despite an average temporal separation of 7 days. Marked cross-pollination was restricted to distances up to 15 m; thus, average rates of cross-pollination above 0.9% were easily managed in small fields. |
| Published in: | European Journal of Agronomy |
| Volume: | 29 |
| Issue: | 1 |
| Pages: | 29 - 32 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2008-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Coexistence, Pollen dispersal, Short-distance cross-pollination, Color marker |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Coexistence, Pollen dispersal, Short-distance cross-pollination, Color marker |
| DBID source: | PP-42050 |
| DOI: | 10.1016/j.eja.2008.02.002 |
| Nebis system number: | 000650747 |
Quantitative trait loci for yield and correlated traits under high and low soil nitrogen conditions in tropical maize
,
Ribaut, Jean-Marcel, Fracheboud, Yvan, Monneveux, Philippe, Bänziger, Marianne, Vargas, Mateo, Jiang, Changjian,
2007
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| Author(s): | Ribaut, Jean-Marcel, Fracheboud, Yvan, Monneveux, Philippe, Bänziger, Marianne, Vargas, Mateo, Jiang, Changjian |
| Title: | Quantitative trait loci for yield and correlated traits under high and low soil nitrogen conditions in tropical maize |
| Abstract: | The first objective of this study was to map and characterize quantitative trait loci (QTL) for grain yield (GY) and for secondary traits under varying nitrogen (N) supply. To achieve this objective, a segregating F2:3 population previously developed for QTL mapping under water-limited conditions was used. The population was evaluated in Mexico under low N conditions in the dry winter season and under low and high N conditions in the wet summer season. From eight QTLs identified for GY under low N conditions, two were also detected under high N conditions. Five QTLs were stable across the two low N environments and five co-localized with QTLs identified for the anthesis-silking interval (ASI) or for the number of ears per plant (ENO) under low N conditions. The percentage of the phenotypic variance expressed by all QTLs for ASI and ENO was quite different when evaluated under low N conditions during the dry winter (40% for ASI and 22% for ENO) and the wet summer seasons (22% for ASI and 46% for ENO). The results suggest optimizing different breeding strategies based on selection index depending on the growing season. Good QTL colocalization was observed for ASI (four QTLs) and ENO (three QTLs) when looking at QTL identified under low N and water-limited conditions in the same population. The results suggest that that both secondary traits can be used in breeding programs for simultaneous improvement of maize against low N and drought stresses. |
| Published in: | Molecular breeding |
| Volume: | 20 |
| Issue: | 1 |
| Pages: | 15 - 29 |
| ISSN: | 1380-3743, 1572-9788 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Drought tolerance, Low nitrogen tolerance, QTL mapping, Zea mays L |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Drought tolerance, Low nitrogen tolerance, QTL mapping, Zea mays L |
| DBID source: | PP-36178 |
| DOI: | 10.1007/s11032-006-9041-2 |
| Nebis system number: | 001430119 |
Root morphology and photosynthetic performance of maize inbred lines at low temperature
,
Hund, Andreas, Richner, Walter, Soldati, Alberto, Fracheboud, Yvan, Stamp, Peter,
2007
>>
| Author(s): | Hund, Andreas, Richner, Walter, Soldati, Alberto, Fracheboud, Yvan, Stamp, Peter |
| Title: | Root morphology and photosynthetic performance of maize inbred lines at low temperature |
| Abstract: | At low temperature, as occurs in the spring, a high photosynthetic performance of maize (Zea mays L.) in combination with a large leaf area is an important measure for early vigor. However, little is known about adaptation of root morphology to low-temperature conditions. The objectives were (i) to characterize a set of 21 modern inbred lines for photosynthesis-related traits and root morphology at 15/13 °C (day/night) and (ii) elucidate relationships between shoot and root traits. Plants were grown in sand substrate until the two-leaf (V2) stage; the operating efficiency of photosystem II (ΦPSII), chlorophyll content (SPAD), and leaf area were used to estimate the rate of CO2 assimilation per plant (). The genotypes were separated as follows: those that maximize leaf area and those that maximize ΦPSII. The morphological organization of the root systems of the genotypes varied to a great extent. Using a principal component analysis (PCA) of root traits (i.e. length of the primary, seminal, and crown roots), genotypes with homogeneous (similar primary and seminal roots) and heterogeneous (lateral roots of the primary root generally longer than the lateral roots of the seminal roots) root systems were identified. The length of the primary lateral roots was most closely associated with all -related traits and with high plant dry weight. Therefore, most of the genotypes with an heterogeneous root system outperformed those with an homogeneous root system with regard to dry matter accumulation and photosynthetic performance. In conclusion, differences in the organization of the embryonic root system are associated with early vigor. |
| Published in: | European journal of agronomy |
| Volume: | 27 |
| Issue: | 1 |
| Pages: | 52 - 61 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Root morphology, Chilling stress, Chlorophyll fluorescence, Zea mays |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Root morphology, Chilling stress, Chlorophyll fluorescence, Zea mays |
| DBID source: | PP-36176 |
| DOI: | 10.1016/j.eja.2007.01.003 |
| Nebis system number: | 000650747 |
Legume cover crops as living mulches for winter wheat
,
Hiltbrunner, Jürg, Liedgens, Markus, Bloch, Lucia, Stamp, Peter, Streit, Bernhard,
2007
>>
| Author(s): | Hiltbrunner, Jürg, Liedgens, Markus, Bloch, Lucia, Stamp, Peter, Streit, Bernhard |
| Title: | Legume cover crops as living mulches for winter wheat |
| Subtitle: | Components of biomass and the control of weeds |
| Abstract: | To gain information about the possible use of legume cover crops as an alternative and sustainable weed-control strategy for winter wheat (Triticum aestivum L.), an experiment was conducted at two sites in the Swiss Midlands in 2001/2002. Under organic farming conditions winter wheat was direct-drilled into living mulches established with four different legume genotypes or into control plots without cover crops. Compared to NAT (control plots without cover crops but with a naturally establishing weed community), white clover (Trifolium repens L.), subclover (Trifolium subterraneum L.), and birdsfoot trefoil (Lotus corniculatus L.) reduced the density of monocotyledonous, dicotyledonous, spring-germinating, and annual weeds by the time of wheat anthesis. Strong-spined medick (Medicago truncatula Gaertner) was less efficient in this regard. While the grain yield was reduced by 60% or more for all legumes when compared to NOWEED (control plots kept weed-free), a significant negative correlation between the dry matter of the cover crop and weeds as well as between the cover crop and the winter wheat was observed by the time of wheat anthesis. The effect of manuring (60 m3 ha−1 liquid farmyard manure) was marginal for weeds and cover crops but the additional nutrients significantly increased total winter wheat dry matter and grain yields. The suppression achieved by some legumes clearly demonstrates their potential for the control of weeds in such cropping systems. However, before living legume cover crops can be considered a viable alternative for integrated weed management under organic farming conditions, management strategies need to be identified which maximise the positive effect in terms of weed control at the same time as they minimise the negative impact on growth and yield of winter wheat. |
| Published in: | European journal of agronomy |
| Volume: | 26 |
| Issue: | 1 |
| Pages: | 21 - 29 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Cover crop, Legume, Living mulch, Organic farming, Weed, Winter wheat |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Cover crop, Legume, Living mulch, Organic farming, Weed, Winter wheat |
| DBID source: | PP-36168 |
| DOI: | 10.1016/j.eja.2006.08.002 |
| Nebis system number: | 000650747 |
Are seeding densities an opportunity to increase grain yield of winter wheat in a living mulch of white clover?
,
Hiltbrunner, J., Streit, B., Liedgens, M.,
2007
>>
| Author(s): | Hiltbrunner, J., Streit, B., Liedgens, M. |
| Title: | Are seeding densities an opportunity to increase grain yield of winter wheat in a living mulch of white clover? |
| Abstract: | Optimum plant densities are a key to maximise yields in most crops. However, such information is often lacking for more environmentally sound cropping systems, such as living mulches (LM) for small grains. In 2004 and 2005, three trials were conducted in the Swiss Midlands on fields managed in accordance with the Swiss organic farming guidelines. The objective of the study was to determine whether seeding density of winter wheat (Triticum aestivum L.) is a relevant factor for determining grain yield in a white clover (Trifolium repens L.) living mulch. The winter wheat cv. Titlis was directly sown in wide spaced rows (0.375 m) at densities of 300 (LM300), 450 (LM450) or 600 (LM600) viable grains m−2 in a white clover living mulch established at a seeding rate of 15 kg ha−1. A bare soil control treatment with a wheat density of 450 viable grains m−2 (BS450) was also included in the trials. Mean grain yields of LM300, LM450, and LM600 never reached the values observed in BS450. This was mainly due to a lower ear density, which, nevertheless, increased linearly with the seeding density within the living mulch in all trials, but the rate of increase depended on the environment. The decrease of the grain weight brought about by the increasing seeding density had only a marginal impact on the grain yield, which was increased from 1.31, 1.98, and 4.09 Mg ha−1 (LM300) to 1.97, 2.64, and 4.75 Mg ha−1 (LM600) for each of the three trials in the study. Significantly higher protein contents were observed for LM300 compared to the higher densities in the living mulch and to BS450. Our research showed that an increase of the seeding density is an effective mean to increase the grain yield in living mulch systems with white clover. However, it is likely that the control of the living mulch to reduce competition with the main crop is a more relevant factor. |
| Published in: | Field crops research |
| Volume: | 102 |
| Issue: | 3 |
| Pages: | 163 - 171 |
| ISSN: | 0378-4290 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Winter wheat, Triticum aestivum L., White clover, Trifolium repens L., Living mulch, Yield components, Organic farming |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Winter wheat, Triticum aestivum L., White clover, Trifolium repens L., Living mulch, Yield components, Organic farming |
| DBID source: | PP-36174 |
| DOI: | 10.1016/j.fcr.2007.03.009 |
| Nebis system number: | 000002745 |
Response of weed communities to legume living mulches in winter wheat
,
Hiltbrunner, J., Jeanneret, P., Liedgens, M., Stamp, P., Streit, B.,
2007
>>
| Author(s): | Hiltbrunner, J., Jeanneret, P., Liedgens, M., Stamp, P., Streit, B. |
| Title: | Response of weed communities to legume living mulches in winter wheat |
| Abstract: | In order to obtain information about the impact of legume cover crops on the weed community in organic farming, winter wheat (Triticum aestivum L.) was directly drilled in rows 0.1875 and 0.3750 m apart in living mulches that consisted of Trifolium repens L. (TRFRE), T. subterraneum L. (TRFSU), Medicago truncatula Gaertner (MEDTR), and Lotus corniculatus L. (LOTCO). A control treatment without cover crops (NAT, the site-specific weed community) was also established. The vegetation between the wide rows was either mulched or left undisturbed. The effect of liquid farmyard manure (60 m3 ha−1) was also tested. TRFRE, TRFSU, and LOTCO effectively suppressed Poa annua L. and Matricaria recutita L. at site 1 and P. annua, Capsella bursa-pastoris (L.) Med., and Stellaria media (L.) Vill. at site 2 when compared with NAT. MEDTR, which died during the winter, provided little weed suppression. Mulching significantly suppressed dicotyledonous weed species, but favoured Poa trivialis L. No manure effect was observed. Winter hardy legume cover crops contribute to weed suppression in winter wheat. However, careful evaluation of cover crop × weed × management interactions is necessary to understand the risk for the establishment of problematic weeds. |
| Published in: | Journal of agronomy and crop science |
| Volume: | 193 |
| Issue: | 2 |
| Pages: | 93 - 102 |
| ISSN: | 0931-2250, 0044-2151, 1439-037X |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | legumes, living mulch, multivariate analysis, organic farming, weed community, winter wheat |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | legumes, living mulch, multivariate analysis, organic farming, weed community, winter wheat |
| DBID source: | PP-36166 |
| DOI: | 10.1111/j.1439-037X.2007.00250.x |
| Nebis system number: | 000033963 |
Interannual variability in root growth of spring wheat (Triticum aestivum L.) at low and high nitrogen supply
,
Herrera, Juan M., Stamp, Peter, Liedgens, Markus,
2007
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| Author(s): | Herrera, Juan M., Stamp, Peter, Liedgens, Markus |
| Title: | Interannual variability in root growth of spring wheat (Triticum aestivum L.) at low and high nitrogen supply |
| Abstract: | Little is known about the spatial and temporal characteristics of the root growth of spring wheat and its modification by nitrogen (N) supply. For 4 years the cultivar Toronit was fertilized with 20 (LN) or 270 kg N ha−1 (HN) in lysimeters. The shoot traits were measured at harvest, while root growth was screened regularly at 10 soil depths in minirhizotrons between 0.05 and 1.00 m. The cumulative number of roots cm−2 (CNR) was fitted to a logistic equation to study the course of root growth at each soil depth. Furthermore, the vertical patterns of CNR were examined at the beginning of tillering, stem elongation, anthesis and physiological maturity by a non-parametric regression (splines). The parameters of the logistic and non-parametric models were influenced by all the factors; thus the root system was highly plastic. Whereas the N off take was similar at LN in 1999, 2001 and 2002, the period of linear increase in CNR in the subsoil was 7 d longer in 2001 than in 2002. At HN, the N off take was higher in 1999 than in 2001 but the reverse was true for root growth. There was also variation among years in the total duration of root growth, with differences up to 20 d. The percentage of roots grown after anthesis ranged from 1 to 22% of the total roots grown by physiological maturity, demonstrating that the root growth of spring wheat can be high and variable after anthesis. This percentage differed among years more in the subsoil and supported the evidence provided by the time parameters of the logistic equation that the impact of climatic and soil conditions on root growth seems to become stronger with time. At all levels of N supply, the vertical pattern of CNR was characterized by an exponential decrease at the beginning of tillering in all the years. Such a clear pattern was not found at later developmental stages. Though the basic knowledge of the variability of root growth of spring wheat increased, the interannual variability in root dynamics was not explained fully by climatic differences among the growing seasons. |
| Published in: | European journal of agronomy |
| Volume: | 26 |
| Issue: | 3 |
| Pages: | 317 - 326 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Wheat, Nitrogen, Root, Development, Growth, Soil |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Wheat, Nitrogen, Root, Development, Growth, Soil |
| DBID source: | PP-36165 |
| DOI: | 10.1016/j.eja.2006.11.003 |
| Nebis system number: | 000650747 |
Dynamics of root development of spring wheat genotypes varying in nitrogen use efficiency
,
Herrera, J. M., Stamp, P., Liedgens, M.,
2007
>>
| Author(s): | Herrera, J. M., Stamp, P., Liedgens, M. |
| Title: | Dynamics of root development of spring wheat genotypes varying in nitrogen use efficiency |
| Abstract: | Three spring wheat genotypes (cv. Albis and Toronit and the experimental line L94491) identified to vary in nitrogen use efficiency characteristics, were studied in lysimeters under two levels of N supply (0 and 250 Kg N ha-1) in 1999 and 2000. No. of roots cm-2 were obtained from regular minirhizotron observations at soil depths of 0.10, 0.25, 0.45, 0.80 and 1.00 m and fitted to a logistic equation. The parameters of the logistic model were influenced by all study factors, indicating a high plasticity of the root system of spring wheat to respond to different soil conditions. A single main genotype effect was observed among all tested factors: the asymptotic no. of roots cm-2 was significantly higher for Toronit than Albis and especially L94491 in the topsoil (0.10 and 0.30 m). Contrastingly, the N supply modified the asymptotic growth in 1999 at 0.10 m and in both years at 0.25 m as well as the root growth pattern at 0.80 in 1999 and at 0.10 m and 0.25 m soil depth in both years. |
| Book title: | Wheat Production in Stressed Environments : proceedings of the 7th International Wheat Conference, 27 November-2 December 2005, Mar del Plata, Argentina |
| Published in: | Developments in plant breeding |
| Volume: | 12 |
| Pages: | 197 - 201 |
| ISBN: | 978-1-4020-5496-9, 978-1-4020-5497-6, 1-4020-5496-3 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Acker- und Futterbau (inkl. Kultur- und Nutzpflanzen) | Crop and Fodder Farming (incl. Cultivated and Crop Plants), root development, nitrogen |
| Event name: | 7th International Wheat Conference (7 IWC) |
| Event date: | November 27 - December 2, 2005 |
| Place: | Mar del Plata, Argentina |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | root development, nitrogen |
| DBID source: | PP-36164 |
| DOI: | 10.1007/1-4020-5497-1_25 |
| Nebis system number: | 005427717 |
Effect of the 1BL.1RS translocation on the wheat endosperm, as revealed by proteomic analysis
,
Gobaa, Samy, Bancel, Emmanuelle, Kleijer, Geert, Stamp, Peter, Branlard, Gerard,
2007
>>
| Author(s): | Gobaa, Samy, Bancel, Emmanuelle, Kleijer, Geert, Stamp, Peter, Branlard, Gerard |
| Title: | Effect of the 1BL.1RS translocation on the wheat endosperm, as revealed by proteomic analysis |
| Abstract: | The introduction of the 1RS chromosome of rye into wheat made wheat more resistant to several pathogens. Today, this resistance has been overcome but the 1BL.1RS translocation remains interesting because of the improved yield and despite the lower rheological properties it produces. Nothing has been reported yet on the impact of rye chromatin introgression on the grain proteome of wheat. The comparison of the 2-DE profiles of 16 doubled haploid lines, with or without the 1BL.1RS translocation, revealed quantitative and qualitative proteic variations in prolamins and other endosperm. proteins. Eight spots were found specifically in lines having the 1BL.1RS translocation; 16 other spots disappeared from the same lines. Twelve spots, present in both genotypes, met the criteria for up- or down-regulated spots. In translocated genotypes, a highly overexpressed spot, identified as a gamma-gliadin with nine cysteine residues, suggests that the lack of LMW-GS induced by 1BL.1RS is counterbalanced by an overexpression of a relatively similar prolamin. Moreover, a spot that was absent from 1BL.1RS genotypes was identified as a dimeric alpha-amylase inhibitor. It was considered to be a valuable candidate to explain the sticky dough associated with translocated cultivars. |
| Published in: | Proteomics |
| Volume: | 7 |
| Issue: | 23 |
| Pages: | 4349 - 4357 |
| ISSN: | 1615-9853, 1615-9861 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Weinheim |
| Publication status: | Published |
| Subjects: | 1BL.1RS translocation, prolamins, wheat |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | 1BL.1RS translocation, prolamins, wheat |
| DBID source: | PP-36157 |
| DOI: | 10.1002/pmic.200700488 |
| Nebis system number: | 004185633 |
2.., a new high molecular weight glutenin subunit coded by Glu-A1
,
Gobaa, S., Kleijer, G., Stamp, P.,
2007
>>
| Author(s): | Gobaa, S., Kleijer, G., Stamp, P. |
| Title: | 2.., a new high molecular weight glutenin subunit coded by Glu-A1 |
| Subtitle: | Its predicted structure and its impact on bread-making quality |
| Abstract: | The suitability of wheat varieties for bread-making depends on their glutenin subunits. The amino acid composition of these gluten building-blocks have a strong influence on the rheology of the dough and, thus, on the suitability of the variety for bread-making. This study reports a new x-type high molecular weight glutenin subunit coded by the locus Glu-A1 and named 2 center dot center dot. To investigate the impact of this allele on 10 quality parameters, a doubled haploid (DH) population of Triticum aestivum, segregating for Glu-A1, was created. The statistical analysis demonstrates that, at Glu-A1, the subunit 2 center dot center dot is as favourable for quality as the subunit 2*. This is in accordance with results showing that the 2 center dot center dot open reading frame still has the same number of cysteines as 2*. The small differences in the length of the central domain had no detectable effect on the elasticity, tenacity and baking quality, of the dough. |
| Published in: | Plant breeding |
| Volume: | 126 |
| Issue: | 1 |
| Pages: | 1 - 4 |
| ISSN: | 0179-9541, 1439-0523 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Triticum aestivum, glutenin, Glu-A1, allele, Ax2.., bread-making quality |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Triticum aestivum, glutenin, Glu-A1, allele, Ax2.., bread-making quality |
| DBID source: | PP-36162 |
| DOI: | 10.1111/j.1439-0523.2006.01313.x |
| Nebis system number: | 000034603 |
The Technological Gap for Maize Cultivation and Soil Properties in a Watershed of Guatemala
,
Fournier, J. M., Stamp, P., Bolaños, J.,
2007
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| Author(s): | Fournier, J. M., Stamp, P., Bolaños, J. |
| Title: | The Technological Gap for Maize Cultivation and Soil Properties in a Watershed of Guatemala |
| Abstract: | The technological gap is wide between potential and actual maize yields in the tropics. An estimation and explanation of the existing yield gap in a model region of Guatemala were attempted. Experiments were carried out on the hypothesis that soil constraints like lack of nutrients exist on 74 farms in four seasons from 1996 to 1998. The hybrid HB-83 was compared with local varieties. Treatments included no fertilizer or the application of recommended and supra optimum amounts of fertilizers. The P and K availability was low. At the site with the lowest yield potential, HB-83 yielded 65 % more than the local varieties, while at the site with the highest yield potential, this relative yield advantage was only 28 %. However, the absolute yield difference between HB-83 and the local varieties was 70 % higher at the site with the highest yield potential compared with the site with the lowest yield potential, with grain yields ranging from 5.21 to 0.29 t ha−1 for local varieties. There were few significant correlations between soil parameters and plant traits. Plant nutrient constraints besides NPK and liming did not seem to limit the yield potential in the Polochic watershed. A combination of soil management practices, liming in association with corrected levels of P, and use of crop cultivars developed for these low pH conditions could lead to sustainable and productive maize production. |
| Published in: | Journal of agronomy and crop science |
| Volume: | 193 |
| Issue: | 6 |
| Pages: | 452 - 460 |
| ISSN: | 0931-2250, 0044-2151, 1439-037X |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | maize, soil properties, technological gap, watershed |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | maize, soil properties, technological gap, watershed |
| DBID source: | PP-36156 |
| DOI: | 10.1111/j.1439-037X.2007.00275.x |
| Nebis system number: | 000033963 |
Cross-pollination of maize at long distance
,
Bannert, Michael, Stamp, Peter,
2007
>>
| Author(s): | Bannert, Michael, Stamp, Peter |
| Title: | Cross-pollination of maize at long distance |
| Abstract: | In a 2-year-study in Switzerland the cross-pollination of maize was investigated by using the occurrence of yellow grains in 13 white grain maize fields as a marker of cross-pollination from neighbouring yellow grain fields. Distances of 50-4500 m between pollen-donor and pollen-receptor fields were investigated. In no case, the cross-pollination of the whole field was more than 0.02%. Four white grain maize fields, located in downwind distances of 50-371 m in the main wind direction, showed low but marked cross-pollination at the field border exposed to the nearest yellow grain maize field. In every field some cross-pollinations with a low rate, on an average of 1.8% of the sampled ears, could be found. These cross-pollinations were mainly single cross-pollinations on the ear. Horizontal wind speed measurements during flowering time in relation to the settling speed of maize pollen showed a potential horizontal pollen dispersal distance of up to 55 m. The few observed cross-pollinations over longer distances could be due to gusts or vertical movements of the wind (e.g., thermal or turbulence effects). In some fields spots of higher cross-pollinations were found. In the cases where the surrounding plants were checked a yellow grain maize seed contamination (0.004% of the seedstock) in the white seeds could be determined as the reason for these "hot-spots". |
| Published in: | European journal of agronomy : the official journal of the European Society for Agronomy |
| Volume: | 27 |
| Issue: | 1 |
| Pages: | 44 - 51 |
| ISSN: | 1161-0301 |
| Publication date / Date received: | 2007-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Landwirtschaft allgemein|Agriculture, General, cross-pollination, coexistence, pollen dispersal, colour marker, maize |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | cross-pollination, coexistence, pollen dispersal, colour marker, maize |
| DBID source: | PP-36154 |
| DOI: | 10.1016/j.eja.2007.01.002 |
| Nebis system number: | 000650747 |
Influence of different weed categories on growth and yields of maize ( Zea mays ) grown in a minor (dry) season of the humid tropics
,
Sangakkara, U.R., Stamp, P.,
2006
>>
| Author(s): | Sangakkara, U.R., Stamp, P. |
| Title: | Influence of different weed categories on growth and yields of maize ( Zea mays ) grown in a minor (dry) season of the humid tropics |
| Abstract: | Weed control is an important management practice in smallholder tropical upland farming systems, and manual weeding is a common feature in these units. This makes selective weeding possible, which is an essential component of integrated weed management. Field studies were initiated in Sri Lanka over a minor (dry) season to determine the impact of different weeds (grasses, broadleaves and sedges) and nonweeded conditions on the growth and yields of maize, cultivated under rainfed conditions. Weed populations were also determined, along with root distribution of the different weed management regimes at anthesis of maize. The presence of all types of weeds or grasses, which was the most dominant weed category, had the greatest adverse impact on growth and yields of maize. The reductions in seed yield due to the presence of all weeds or grasses alone were 59% and 32%, respectively. In contrast, growth and yields of maize was not affected by the small numbers of sedges present. The impact of broadleaved species was lower than that of all weeds or the grasses. Root distribution through the soil profile was greatest when maize was grown with broadleaved species or with all weeds. The roots of the maize-grass mixtures were concentrated in the upper soil layers. The beneficial impact of removing grasses and broadleaved weeds in selective manual weeding in rainfed maize cultivation which could be practiced by smallholder farming units to obtain higher yields are presented. Die Kontrolle von Schadpflanzen gehört zu den wichtigen Tätigkeiten im kleinbäuerlichen Landbau tropischer ochlandregionen und das Jäten ist eine verbreitete Praktik auf solchen Betrieben. Jäten ermöglicht ein selektives Entfernen der Schadpflanzen und gehört zu den essenziellen Bestandteilen einer integrierten Schadpflanzenbekämpfung. Auf Sri Lanka wurden Feldversuche während der Trockenzeit durchgeführt, um den Einfluss verschiedener Schadpflanzengruppen (Gräser, breitblättrige Schadpflanzen und Seggen) und unbehandelter Felder auf den Ertrag von Mais im Regenfeldbau zu bestimmen. Schadpflanzenpopulationen wurden zusammen mit der Wurzelverteilung im Bodenprofil zu Beginn der Maisblüte in den verschiedenen Behandlungsvarianten bestimmt. Das gemeinsame Vorkommen aller Gruppen dikotyler Schadpflanzen und Gräser, die die dominante Gruppe darstellten, hatte den größten negativen Einfluss auf Wachstum und Ertrag von Mais. Die Ertragsverluste beim gemeinsamen Vorkommen aller Schadpflanzengruppen oder nur der Gräser betrugen 59 bzw. 32%. Die in geringer Zahl vorkommenden Seggen verringerten den Ertrag dagegen nicht. Der Einfluss breitblättriger Schadpflanzen war geringer als der der Gräser oder der aller Gruppen gemeinsam. Die urzelverteilung im Bodenprofil war am ausgeprägtesten in Gegenwart von allen Pflanzengruppen gemeinsam oder der breitblättrigen Pflanzen alleine. In ausschließlicher Gegenwart von Schadgräsern wuchsen die Maiswurzeln nur in den obersten Bodenschichten. Die Vorteile einer selektiven Entfernung von Gräsern und breitblättrigen Schadpflanzen, die im kleinbäuerlichen Regenfeldbau von Mais in tropischen Hochlandregionen praktikabel ist, werden dargestellt. |
| Published in: | Journal of plant diseases and protection |
| Volume: | 113 |
| Issue: | 2 |
| Pages: | 81 - 85 |
| ISSN: | 1861-3829, 0340-8159, 1861-3837 |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Stuttgart |
| Publication status: | Published |
| Subjects: | Broadleaves, Grasses, Manual weeding, Sedges, Weeds |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Broadleaves, Grasses, Manual weeding, Sedges, Weeds |
| DBID source: | PP-28154, WOS-000238252800006 |
| Nebis system number: | 000039466 |
Impact of selective weeding on maize productivity in major and minor seasons
,
Sangakkara, U.R., Stamp, P.,
2006
>>
| Author(s): | Sangakkara, U.R., Stamp, P. |
| Title: | Impact of selective weeding on maize productivity in major and minor seasons |
| Subtitle: | A comparative analysis from the Asian humid tropics |
| Abstract: | Weed management is vital in tropical food cropping systems to minimize competition for scare resources, especially under smallholder farming conditions, where hand weeding using family labor is a common feature. Hence, selective weeding could be practiced to maintain weed populations below economic threshold levels, and minimize competition. Field studies were initiated under rainfed conditions of Sri Lanka over the major and minor seasons that correspond to the two monsoons to determine the impact of selective weeding on growth and yields of maize (Zea mays L), the most popular highland cereal in these regions. The lack of weed control measures or the presence of the most abundant grass weeds reduced growth and yields of maize irrespective of the season. The adverse effects of the low number of sedges (Cyperaceae) was minimal, and that of broadleaves was lower than the impact of grasses. Comparative analysis of the effects of weeds in the two seasons highlighted the greater adverse effect in the minor season when the crop is subjected to water stress conditions. The weed numbers were greater, which affected the growth and yields of maize to a greater extent. However, the adverse effects of the different weed types did not change with seasons. The feasibility of adopting selective weeding to minimize adverse effects in rainfed farming systems of the humid tropics for procuring high yields is presented on the basis of this study. In contrast, clean weeding could develop other effects such as erosion. Eine Unkrautkontrolle in tropischen Anbausystemen zur Nahrungsmittelproduktion ist unerlässlich, um die Konkurrenz um die knappen Ressourcen zu minimieren. Dies gilt besonders unter kleinbäuerlichen Bedingungen, wo das Jäten per Hand noch üblich ist. So kann eine selektive Unkrautvernichtung dazu beitragen, die Unkrautpopulation unterhalb der Schadensschwelle zu halten und so die Konkurrenz zu minimieren. In Feldversuchen ohne Bewässerungssystem in Sri Lanka während der Kleinen und der Großen Regenzeit – die mit den beiden Monsunzeiten übereinstimmen – wurde der Einfluss einer selektiven Unkrautentfernung auf das Wachstum und den Ertrag von Mais (Zea mays L), der häufigsten Getreideart in dieser Bergregion, untersucht. Das Fehlen jeglicher Unkrautkontrollmassnahmen oder der Besatz mit den häufigsten Ungräsern beeinträchtigen sowohl das Wachstum als auch den Ertrag unabhängig von der Anbausaison. Seggen und das Vorkommen von breitblättrigen Unkräutern hatten einen geringeren negativen Einfluss als das Vorkommen von Ungräsern. Vergleichende Analysen der Auswirkungen von Unkräutern auf die Produktivität von Mais in den unterschiedlichen Anbauzeiträumen zeigte einen stärkeren Einfluss in der kleinen Regenzeit, wenn die Pflanze einem Wasserstress ausgesetzt ist. Die Unkrautzahlen waren höher, was zu einer stärkeren Reduktion des Wachstums und des Ertrages von Mais führte. Die spezifischen Einflüsse der verschiedenen Unkrautarten werden durch die Anbausaison jedoch nicht verändert. Die Umsetzbarkeit der selektiven Unkrautkontrolle zur Erreichung eines höheren Ertrags in unbewässerten Anbausystemen der feucht-tropischen Regionen Asiens wird unter Berücksichtigung des Vergleichs mit einer totaler Unkrautvernichtung, die zu anderen unerwünschten Effekten wie z.B. Erosion führen kann, diskutiert. |
| Published in: | Journal of plant diseases and protection. Special Issue |
| Volume: | XX |
| Pages: | 701 - 708 |
| ISSN: | 1861-4051 |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Stuttgart |
| Publication status: | Published |
| Subjects: | Weeds, selective weeding, maize, major and minor seasons, humid tropics, Unkräuter, selektive Unkrautbekämpfung, Mais, Große und Kleine Regenzeit, feuchte Tropen |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Weeds, selective weeding, maize, major and minor seasons, humid tropics, Unkräuter, selektive Unkrautbekämpfung, Mais, Große und Kleine Regenzeit, feuchte Tropen |
| DBID source: | PP-28161 |
Interseasonal cropping
,
Sangakkara, U.R., Bandaranayake, P.R.S.D., Weerasekera, D.N.K., Stamp, P.,
2006
>>
| Author(s): | Sangakkara, U.R., Bandaranayake, P.R.S.D., Weerasekera, D.N.K., Stamp, P. |
| Title: | Interseasonal cropping |
| Subtitle: | Its potential for managing weeds in the Asian tropics |
| Abstract: | Tropical farming systems cultivate food and cash crops with the monsoonal rains. Lands are generally left fallow during the interseasonal periods, thus building up weed populations and weed seed banks. Field studies were conducted to determine the impact of managing the interseasonal periods by growing either a food crop or green manures and its impact on weed populations in the subsequent season. The management strategies used after a maize crop in the major season were leaving the land fallow as normal practice, growing Phaseolus beans (a food crop), Crotalaria juncea (a fast growing legume green manure) or Tithonia diversifolia (a slow growing non legume green manure). A crop of mungbean (Vigna radiata L.) was planted in the following minor season and weed populations were monitored, along with crop yields. As expected, the weed populations in plots left fallow were the highest, thus requiring weeding in the mungbean crop on three occasions. Lack of weeding reduced mung bean seed yields by 67 %, when compared to the weeded plots. Growing Crotalaria juncea as legume cover crop resulted in the lowest weed populations in mungbean, thus requiring only one weeding, and the lack of weeding reduced yields only by 18 % as compared to the weeded plots. The slower growing green manure (Tithonia diversifolia ) or the food crop (beans) facilitated a greater population of weeds in the succeeding mungbean crop. The importance of managing the interseasonal fallow periods for better integrated weed management strategies of smallholder tropical farming systems is discussed. In den Tropen werden Nahrungs- und Handelspflanzen während der Regenzeit angebaut. Das Land liegt in der Trockenzeit meist brach und Unkrautpopulationen können sich etablieren und aussamen. In Feldversuchen wurde getestet, welchen Einfluss der Anbau entweder einer Nahrungspflanze oder von Gründüngungspflanzen in der Trockenzeit auf die Unkrautpopulation in der folgenden Anbauperiode haben. Folgende Massnahmen kamen zum Einsatz: Nach Mais in der Regenzeit wurde das Feld nicht bebaut – wie es übliche Praxis ist – oder mit Phaseolus Bohnen (einer Nahrungspflanze), Crotolaria juncea (eine schnell wachsende Leguminose zur Gründüngung) bzw. Tithonia diversifolia (eine langsam wachsende Gründungsungspflanze, keine Leguminose) bebaut. In der folgenden kleinen Regenzeit wurden Mungbohnen angepflanzt und die Zahl der Unkrautpflanzen erhoben und der Ertrag ermittelt. Wie erwartet war der Unkrautbesatz nach der Brache am höchsten und machte drei Unkrautbekämpfungsmassnahmen notwendig. Ohne Unkrautbekämpfung war der Samenertrag der Mungbohne um 67 % reduziert, verglichen mit den gejäteten Flächen. Der Anbau von Crotolaria juncea, der schnell wachsenenden Leguminose hinterliess die geringste Unkrautpopulation in den Mungbohnenkulturen, die nur ein einmaliges Jäten erforderte. Ohne Unkrautbekämpfung wurde der Ertrag nur um 18 % reduziert verglichen zu den Parzellen mit Jäten. Die langsam wachsende Gründüngungspflanze (Tithonia diversifolia) oder die Phaseolusbohne unterdrückten die Unkrautpopulation in der nachfolgenden Kultur weniger gut Die Bedeutung einer Bewirtschaftung der Landfläche während der Trockenzeit für eine besser integrierte Unkrautkontrolle in kleinbäuerlichen Betrieben der Tropen wird diskutiert. |
| Published in: | Journal of plant diseases and protection |
| Volume: | Special Issue XX |
| Pages: | 921 - 927 |
| ISSN: | 1861-3829, 0340-8159, 1861-3837 |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Stuttgart |
| Publication status: | Published |
| Subjects: | Tropics, interseasonal fallow periods, weed management, cropping yields, Tropen, Trockenzeitbrache, Unkrautkontrollmassnahmen, Anbausystem, Ertrag |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Tropics, interseasonal fallow periods, weed management, cropping yields, Tropen, Trockenzeitbrache, Unkrautkontrollmassnahmen, Anbausystem, Ertrag |
| DBID source: | PP-28164, WOS-000243269500003 |
| Nebis system number: | 000039466 |
Impact of tillage on maize rooting in a Cambisol and Luvisol in Switzerland
,
Qin, Ruijun, Stamp, Peter, Richner, Walter,
2006
>>
| Author(s): | Qin, Ruijun, Stamp, Peter, Richner, Walter |
| Title: | Impact of tillage on maize rooting in a Cambisol and Luvisol in Switzerland |
| Abstract: | Soil conditions under no-tillage (NT) are often unfavorable for the growth of maize roots in comparison to conventional tillage (CT). In 1997 and 1999, the impacts of tillage on the morphology and spatial distribution of maize (Zea mays L.) roots at anthesis were investigated in a 5-year field trial at two sites (loamy silt and sandy loam soils) in the Swiss midlands. Four soil cores, perpendicular to the maize row, were taken to a depth of 100 cm in each plot; the root length density (RLD), the mean root diameter (MD), and the relative length per diameter-class distribution (LDD) of the roots were determined. Roots were longer and thinner in 1999 than in 1997. The RLD was significantly higher and the MD was smaller on the loamy silt than on the sandy loam. The RLD and MD decreased with the distance from the plant row. Most of the maize roots, about 80% of the total root length, were in the layer from 0 to 40 cm, with maximum values from 5 to 10 cm; the thickest roots were in the soil layer from 10 to 50 cm. Significant differences in RLD with increasing distance from the row of plants were found in the top 30 cm. Averaged over the whole soil profile, RLD was higher and MD was smaller under CT than under NT. The impact of tillage on RLD and MD interacted with spatial factors and years. Within the soil profile, RLD was significantly higher under NT than under CT at a depth of 5 cm, whereas it was higher under CT than under NT below 10 cm. Below 50 cm, there was no difference in RLD between the tillage systems. In a horizontal direction, MD was consistently higher in the row and lower in the mid-row under NT than under CT. Our results show that differences in maize root growth between tillage systems, which were reported in previous studies, persist until anthesis. The accumulation of maize roots near the soil surface in NT suggests that subsurface-banding of starter fertilizer is a more efficient way of applying fertilizer (particularly immobile nutrients such as phosphorus) compared with broadcasting in order to supply sufficient nutrients for NT maize. |
| Published in: | Soil & tillage research |
| Volume: | 85 |
| Issue: | 1-2 |
| Pages: | 50 - 61 |
| ISSN: | 0167-1987 |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Root morphology, Root distribution, Maize, No-tillage, Conventional tillage |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Root morphology, Root distribution, Maize, No-tillage, Conventional tillage |
| DBID source: | PP-28150, WOS-000234146700005 |
| DOI: | 10.1016/j.still.2004.12.003 |
| Nebis system number: | 000009865 |
Swiss maize landraces
,
Peter, R., Eschholz, T.W., Stamp, P., Liedgens, M.,
2006
>>
| Author(s): | Peter, R., Eschholz, T.W., Stamp, P., Liedgens, M. |
| Title: | Swiss maize landraces |
| Subtitle: | Early vigour adaptation to cool conditions |
| Abstract: | Due to their good early vigour, Swiss maize landraces have been used extensively to develop the Flint Pool of European hybrid-breeding programmes. However, the basis of good early vigour, especially under cool conditions, has not been elucidated. Of 166 pre-screened Swiss maize landraces, 17 contrasting accessions were tested together with two control accessions, a German landrace and a modern hybrid cultivar with proven good early vigour, at sites in the midlands and the foothills of the Alps in Switzerland. To investigate early vigour, photosynthesis, leaf greenness and plant growth were recorded. Compared to the modern standard hybrid cultivar, northern accessions showed superior early vigour under cold stress in the field for all traits examined in these experiments, whereas these traits were much less pronounced in southern accessions. In particular, some accessions from the Rhine valley seem to be promising sources of early vigour for use in breeding programmes. These findings support the hypothesis that long-term selection resulted in the adaptation of maize landraces to their local environment. Compared to the phylogenetic tree, it is evident that accessions with superior early vigour are related to each other and originated in the Rhine valley. |
| Published in: | Acta agronomica Hungarica |
| Volume: | 54 |
| Issue: | 3 |
| Pages: | 329 - 336 |
| ISSN: | 1588-2527, 0238-0161 |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Budapest |
| Publication status: | Published |
| Subjects: | flint maize, Zea mays L., cold tolerance, landraces, early vigour |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | flint maize, Zea mays L., cold tolerance, landraces, early vigour |
| DBID source: | PP-28145 |
| DOI: | 10.1556/AAgr.54.2006.3.7 |
Effects of pre-anthesis drought, nitrogen fertilizer rate, and variety on grain yield, yield components, and harvest index of tropical maize
,
Moser, Samuel B., Feil, Boy, Jampatong, Sansern, Stamp, Peter,
2006
>>
| Author(s): | Moser, Samuel B., Feil, Boy, Jampatong, Sansern, Stamp, Peter |
| Title: | Effects of pre-anthesis drought, nitrogen fertilizer rate, and variety on grain yield, yield components, and harvest index of tropical maize |
| Abstract: | Water and nitrogen (N) are the most limiting factors for grain yield of maize (Zea mays L.) in the tropics. In Thailand, the risk of water shortage is highest during the vegetative stages of maize development. A 3-year study with two water regimes (pre-anthesis drought versus irrigation throughout the vegetation cycle), three levels of N fertilization (0, 80, and 160 kg N ha−1), two open-pollinated varieties (Suwan 1 and La Posta Sequia), and two hybrids (KTX2602 and DK888) was conducted to determine the interactive effects of pre-anthesis water supply, N fertilizer rate, and variety on the grain yield, yield components, and harvest index of maize in the tropical lowlands of Thailand. Averaged across the N rates and varieties, drought-stressed maize yielded 32% (1995), 13% (1996), and 21% (1997) less than well-watered maize. Irrespective of variety, 80 kg N ha−1 was sufficient to achieve maximum grain yield under pre-anthesis drought, whereas 160 kg N ha−1 resulted in the highest yield under well-watered conditions. Pre-anthesis drought significantly reduced the number of kernel rows, the number of kernels per row, as well as the 1000-kernel weight. The effect of the water regime on the ear number of DK888 varied from year-to-year. Water stress consistently resulted in increases in the harvest index. There were significant effects of the water regime × variety interaction on grain yield in two of the three cropping seasons. KTX2602 was more affected by drought than Suwan 1 in all the years and, in 2 of the 3 years, than La Posta Sequia. This was attributed to the fact that KTX2602 was the earliest variety. In 1996, DK888, the top yielder, produced almost the same grain yield under drought stress and continuous irrigation. Unfavorable weather conditions shortly after silking in 1996 (low irradiation in combination with relatively high temperature) seemed to have limited the grain yield of well-watered DK888. It is hypothesized that the adverse effects of pre-anthesis drought on grain yield can be mitigated if varieties are selected for roots which rapidly penetrate the soil and exploit the water resources in deep soil layers. |
| Published in: | Agricultural water management |
| Volume: | 81 |
| Issue: | 1-2 |
| Pages: | 41 - 58 |
| ISSN: | 0378-3774 |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Amsterdam |
| Publication status: | Published |
| Subjects: | Landwirtschaft allgemein|Agriculture, General, Harvest index, Tropical maize, Nitrogen fertilization, Pre-anthesis water stress, Yield components |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Harvest index, Tropical maize, Nitrogen fertilization, Pre-anthesis water stress, Yield components |
| DBID source: | PP-28142, WOS-000235861100003 |
| DOI: | 10.1016/j.agwat.2005.04.005 |
| Nebis system number: | 000000988 |
The genetic dissection of key factors involved in the drought tolerance of tropical maize (Zea mays L.)
,
Messmer, Rainer Ernst,
2006
>>
| Author(s): | Messmer, Rainer Ernst |
| Title: | The genetic dissection of key factors involved in the drought tolerance of tropical maize (Zea mays L.) |
| Abstract: | Maize is an important source of human nutrition, especially in the tropics, where most of the maize is grown under rain-fed conditions and where drought is a major constraint to agricultural production. Sub-Saharan Africa is currently one of the most severely affected regions and the occurrence of drought spells is predicted to increase in the future. The development of more drought-tolerant genotypes can contribute to ensure food security in this area and worldwide. However, selection for drought tolerance is difficult because of the unpredictability of stress under natural conditions, because of the occurrence of strong interactions between genotypes and the environment and because of limited knowledge about the role and regulation of tolerance mechanisms. Classical approaches to breeding have identified secondary traits for grain yield under drought stress. Most of these traits are polygenic, but grain yield probably remains the most polygenic and complex trait. The genetic control of polygenic and complex traits is mainly quantitative. The mapping of quantitative trait loci (QTLs) is, therefore, a promising tool for detecting genomic regions controlling polygenic trait expression as well as for studying changes in the expression of these loci across varying environmental conditions. The goal of this project was to provide an understanding of the genetic basis of morphological and physiological traits involved in response to water-limited conditions at flowering of two tropical maize lines with different levels of drought tolerance. The target regions identified by QTL mapping will contribute to complementing the evaluation and selection of improved germplasm, especially in sub-Saharan Africa. To achieve this goal, a genetic linkage map was constructed for a population of recombinant inbred lines (RILs). These lines were developed by crossing the drought-tolerant tropical maize line CML444 (PL1) with the droughtsusceptible tropical maize line SC-Malawi (PL2) and five generations of inbreeding. The genetic linkage map consisted of the allelic segregation of 236 RILs at 160 molecular marker loci. The map was 2105 cM long and had an average distance between two consecutive markers of 13.2 cM. The RIL population and the parental lines were evaluated in a total of 11 field experiments in Mexico and Zimbabwe. The experiments were performed in 2003 and 2004 under managed drought stress at flowering (D) or under rain-fed conditions (W) with sufficient water supply. The plants were phenotyped for flowering time, plant height, chlorophyll content of two leaves, leaf senescence and root capacitance as well as for the dry weight of the tassels, ears and silks during the critical stress period; grain yield parameters were measured at maturity. The QTLs were identified by composite interval mapping. Drought stress caused large reductions in total grain yield and, correlatively, in kernel number per area compared to the highest-yielding experiment under rain-fed conditions in Zimbabwe (WZ1). Grain yield (GYA) was controlled by only a few QTLs, whose effects on trait expression were larger and more significant under rain-fed conditions than under drought. The QTLs for GYA showed strong interactions with the environment (QEI) and changed their positions on the genome across environments. The strong genetic control of hundred kernel weight (HKW), in contrast, was stable and unrelated to that of grain yield. The anthesis-silking interval (ASI), a common secondary trait for grain yield under drought, was negatively correlated with GYA both within and across experiments. However, QTLs with direct effects on both traits were not observed under drought stress. The QTL on chromosome 1 close to marker 15 (c1m15) was the only locus that controlled ASI in more than one environment. It was detected between the QTL c1m11, with a large positive additive effect on grain yield in the high-yielding and rain-fed experiment in Zimbabwe and with negative effects on plant height (PHT) in the other environments, and the QTL c1m17 controlling male flowering time (MFL) and ear dry weight at anthesis (EW0). Contrary to expectations, the allele of the drought-tolerant parent (PL1) was associated with an increase in ASI, which is unfavorable under drought stress. The effect of these QTLs on chromosome 1 on trait expression demonstrated that GYA was more closely associated genetically with PHT and that ASI was more closely related with MFL than was GYA with ASI in this tropical maize population. The PL1 realized its high yield potential only under rainfed conditions and showed larger drought-induced yield reductions than PL2. Nevertheless, PL1 produced more grains than PL2 in the drought-stress experiments, but the differences between the two lines were smaller than in the rain-fed experiments and not always significant. Drought stress concomitantly reduced the PHT of PL1 to a greater extent than the PHT of PL2; MFL of PL1 was delayed. Apparently, PL2 escaped drought stress through early maturity when exposed to water-limited conditions at flowering. Considering these distinct phenotypic responses of the two parental lines to water shortage, the QTLs for GYA, PHT, ASI, MFL and EW0, detected on chromosomes 1 and 3, but also the QTLs for MFL and leaf chlorophyll content on chromosome 2, revealed the important genetic basis of the morpho-physiological differences between the two parental lines. Each of the morpho-physiological traits evaluated in this study, including root capacitance (RCT) and tassel dry weight (TBW), was controlled by at least one QTL detected in more than one environment, which suggested that all the traits were controlled by some intrinsic genes. However, not all of these genes were constitutively expressed in all experiments. MFL, in particular, was under strong genetic control. The four most important QTLs for this trait corresponded to universal QTLs for flowering time in maize. TBW did not influence MFL, but there was a weak negative correlation between TBW and ear dry weight at anthesis (EW0). This correlation suggested that selection for small tassels could increase the flux of assimilates to the ear before and during the critical period at flowering. However, such an effect would be small, because the phenotypic correlation was weak and the dry weight of the male and the female inflorescences were controlled by distinct QTLs. The phenotypic response of the parental lines to drought stress in terms of EW0 showed notable similarities to GYA. The phenotypic differences between the two lines were largest under rain-fed conditions and PL1 showed larger drought-stress-induced reductions in EW0 than PL2. Nevertheless, the QTL c3m7, important for the dry weight of the ears and silks at flowering under drought-stressed conditions, was not detected for grain yield. Co-locating QTLs for grain yield and for physiological secondary traits, such as the anthesis-silking interval, dry weight of the ears and silks at anthesis, leaf chlorophyll content and leaf senescence, but also for plant height were observed on chromosomes 8, 9 and 10. The pattern of QTL expression across experiments, together with the additive effects of the PL1 allele, suggested the presence of stress-adaptive genes. Their effect on drought-tolerance mechanisms contrasted with the effect of the rather structural and constitutive QTLs located on chromosomes 1, 2 and 3. Therefore, the middle sections of chromosomes 8, 9 and, in particular, the middle section of chromosome 10 were identified as potential target regions for marker-assisted selection (MAS) for improving drought tolerance. The QTL regions on the middle sections of chromosomes 1, 2 and 3 should also be used for MAS, since the effects of the respective QTLs on vegetative growth, organ development and other plant characteristics such as leaf chlorophyll content suggested that functional gene clustering can be expected in maize. This would be an important prerequisite for the development and the successful application of novel MAS techniques without the common drawbacks of MAS, namely cross specificity and the narrow range of target environments. |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Zürich |
| Publication status: | Published |
| Language: | English |
| Review status: | Unknown |
| ETH dissertation number: | 16695 |
| DBID source: | PP-32512 |
| DOI: | 10.3929/ethz-a-005273099 |
| Nebis system number: | 005273099 |
Swiss maize landraces
,
Eschholz, T.W., Peter, R., Stamp, P., Hund, A.,
2006
>>
| Author(s): | Eschholz, T.W., Peter, R., Stamp, P., Hund, A. |
| Title: | Swiss maize landraces |
| Subtitle: | Their diversity and genetic relationships |
| Abstract: | Genetic variation in the flint maize (Zea mays L. conv. indurata) gene pool has decreased significantly since the introduction of hybrid breeding into Europe in the 1950s, leading to greater genetic vulnerability. Landraces, stored in gene banks, offer a valuable source to broaden the genetic basis again. The objective of this study was the genetic characterization of 166 Swiss landrace accessions originating from 7 Swiss regions (alpine valleys). The material was fingerprinted using a set of ten SSRs (Simple Sequence Repeat Markers). The resulting cladogram showed three main clusters comprising 95, 22 and 49 accessions, respectively. The largest group of accessions, from the Rhine valley of St. Gallen (RT), was present in all three main clusters. However, the majority of RT accessions was found in the first main cluster, together with those from the western neighbouring region (Linthtal) and from the southwestern neighbouring region (Wallis). Those from Tessin (southern Switzerland) were found mainly in one sub-cluster within the third main cluster. This is a very encouraging first step in appraising the genetic differences among accessions from Swiss regions. |
| Published in: | Acta agronomica Hungarica |
| Volume: | 54 |
| Issue: | 3 |
| Pages: | 321 - 328 |
| ISSN: | 1588-2527, 0238-0161 |
| Publication date / Date received: | 2006-01-01 |
| Publication status: | Budapest |
| Publication status: | Published |
| Subjects: | Switzerland, flint maize, genetic distance, Zea mays L., SSR markers, landraces |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Switzerland, flint maize, genetic distance, Zea mays L., SSR markers, landraces |
| DBID source: | PP-28130 |
| DOI: | 10.1556/AAgr.54.2006.3.6 |
Maize yields as affected by short- and long-term improved fallows
,
Schelbert, R., Sangakkara, U.R., Stamp, P.,
2005
>>
| Author(s): | Schelbert, R., Sangakkara, U.R., Stamp, P. |
| Title: | Maize yields as affected by short- and long-term improved fallows |
| Subtitle: | A comparative analysis in the Asian humid tropics |
| Abstract: | Improved short- or long-term fallows are considered suitable low external input technologies for maintaining productivity and sustainability of tropical smallholder upland cropping units, although comparisons on the benefits of this technology are not widely reported. A field study evaluated the impact of improved short (6 months) and long-term fallow (18 months) using Crotalaria juncea and Tithonia diversifolia, in relation to a natural fallow of the same durations, on the productivity of maize (Zea mays), the most important upland cereal in tropical Asia, over a minor season. The use of improved fallows, especially Tithonia, increased maize yields over the Crotalaria or natural fallow. While the overall yields of maize after a long fallow were greater, the beneficial impact of the green manures was significantly higher in the short fallows. The causal factors for this trend, including biomass production of the improved fallows and possible impact on soils, along with the greater benefits of short-term fallows for increasing maize yields in the tropics due to lower requirements of unproductive time are presented. |
| Published in: | Journal of agronomy and crop science |
| Volume: | 191 |
| Issue: | 6 |
| Pages: | 411 - 415 |
| ISSN: | 0931-2250, 0044-2151, 1439-037X |
| Publication date / Date received: | 2005-01-01 |
| Publication status: | Berlin |
| Publication status: | Published |
| Subjects: | Crotalaria, fallow periods, maize, Tithonia, yields |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | Crotalaria, fallow periods, maize, Tithonia, yields |
| DBID source: | PP-17728 |
| DOI: | 10.1111/j.1439-037X.2005.00183.x |
| Nebis system number: | 000033963 |
Prediction of maize grain yield using the chlorophyll meter technique in the Polochic Watershed of Guatemala
,
Fournier, Jerome Marc, Stamp, Peter, Bolanõs, Jorge,
2004
>>
| Author(s): | Fournier, Jerome Marc, Stamp, Peter, Bolanõs, Jorge |
| Title: | Prediction of maize grain yield using the chlorophyll meter technique in the Polochic Watershed of Guatemala |
| Abstract: | Growers of tropical maize (Zea mays L.) are often reluctant to invest in seeds and fertilizers because they are seeking to minimize risks. A chlorophyll meter measures leaf greenness, which non-destructively indicates the leaf N concentration. This may be an alternative to sampling N in the soil and to analyzing N in plant tissue, both of which are costly methods for estimating the N status of a crop at a certain growth stage. Thus, at earlier growth stages, the N status of a crop could be related to the final yield. At early growth stages of maize, the chlorophyll meter has been used successfully to predict the yield in many regions. In this study, a Minolta chlorophyll meter (type SPAD 502) was calibrated to distinguish between two maize varieties [Local Variety and HB-83 (a white hybrid)] and three fertilizer treatments [zero, recommended (89:13:24 N:P:K kg ha(-1)), and supra optimum (151:37:76)]. The meter was more useful at lower than at higher levels of fertilization, where SPAD readings as estimates of chlorophyll content appeared to reach a plateau. Both linear and quadratic relationships were observed between SPAD readings and maize grain yields. Central American farmers often apply low levels of fertilizers. If chlorophyll meter readings were to diagnose N deficiency accurately and inexpensively, fertilizers could be applied late in the season to counteract N deficiency. The chlorophyll meter should be calibrated for each variety in order to predict the yield with sufficient precision. |
| Published in: | Tropical agriculture |
| Volume: | 81 |
| Issue: | 2 |
| Pages: | 95 - 100 |
| ISSN: | 0041-3216 |
| Publication date / Date received: | 2004-01-01 |
| Publication status: | Trinidad |
| Publication status: | Published |
| Subjects: | maize, grain yield prediction, N deficiency, minolta chlorophyll meter, linear and, quadratic relationships |
| Language: | English |
| Review status: | Peer reviewed |
| Keyword: | maize, grain yield prediction, N deficiency, minolta chlorophyll meter, linear and, quadratic relationships |
| DBID source: | PP-17723, WOS-000202872800006 |
| Nebis system number: | 000000737 |
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